下面列出了android.view.View#requestFocus ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
/**
* In layout, if there is a view that needs to get focus,
* make sure the view is displayed.
*/
private void scrollToFocusViewInLayout() {
if (hasFocus() && !isSmoothScrolling() && mFocusPosition != NO_POSITION) {
View focusView = findViewByPosition(mFocusPosition);
if (focusView != null) {
if (getScrollPosition(focusView, mTwoInts)) {
int maxScrollDistance = getMaxScrollDistance();
int scrollDistance = mTwoInts[0];
if (scrollDistance > 0) {
if (mHorizontalOffset + scrollDistance > maxScrollDistance) {
scrollDistance = maxScrollDistance - mHorizontalOffset;
}
offsetChildrenPrimary(-scrollDistance);
}
if (!focusView.hasFocus()) {
focusView.requestFocus();
dispatchChildSelected();
}
}
} else if (mFocusPosition != NO_POSITION){
scrollToSelection(mBaseRecyclerView, mFocusPosition, mSubFocusPosition, true,
mPrimaryScrollExtra);
}
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = super.onCreateView(inflater, container, savedInstanceState);
closeBtn.setOnClickListener(this);
view.setFocusableInTouchMode(true);
view.requestFocus();
view.setOnKeyListener(new View.OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_UP) {
doClose();
return true;
} else {
return false;
}
}
});
return view;
}
@Override
protected void onFocusChanged(boolean gainFocus, int direction, @Nullable Rect previouslyFocusedRect) {
super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
if (gainFocus) {
// We favor natural focus if we don't want to remember focus AND if previously focused
// rectangle is NOT null. Usually latter condition holds true if simple requestFocus()
// is called and holds false if focus changed during navigation. Overall this is done
// because of backward compatibility - some code is dependent on the fact that
// focused position will be restored if requestFocus() is called and it expects
// to have natural focus when ordinary navigation happens.
boolean favorNaturalFocus = !mRememberLastFocus && previouslyFocusedRect != null;
View lastFocusedView = mFocusArchivist.getLastFocus(this);
if (favorNaturalFocus || lastFocusedView == null) {
requestNaturalFocus(direction, previouslyFocusedRect);
} else {
lastFocusedView.requestFocus();
}
}
}
public void handleMessage(android.os.Message msg) {
View view = (View) msg.obj;
// 显示软键盘
if (msg.what == Constants.INPUT_METHOD_SHOW) {
boolean result = mInputMan.showSoftInput(view, 0);
if (!result && totalTime < Constants.LIMIT_TIME) {
totalTime += Constants.IDLE;
Message message = Message.obtain(msg);
mHandler.sendMessageDelayed(message, Constants.IDLE);
} else if (!isFinish) {
totalTime = 0;
result = view.requestFocus();
isFinish = true;
}
} else if (msg.what == Constants.INPUT_METHOD_DISAPPEAR) {
// 隐藏软键盘
mInputMan.hideSoftInputFromWindow(view.getWindowToken(), 0);
}
}
@Override
public void onContentChanged(Tab tab) {
// If the tab is frozen, both native page and content view are not ready.
if (tab.isFrozen()) return;
View viewToShow = getViewToShow(tab);
if (isShowing(viewToShow)) return;
removeCurrentContent();
LayoutParams lp = (LayoutParams) viewToShow.getLayoutParams();
if (lp == null) {
lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
}
// Weirdly enough, if gravity is not top, top_margin is not respected by FrameLayout.
// Yet for many native pages on tablet, top_margin is necessary to not overlap the tab
// switcher.
lp.gravity = Gravity.TOP;
UiUtils.removeViewFromParent(viewToShow);
addView(viewToShow, CONTENT_INDEX, lp);
viewToShow.requestFocus();
}
@SuppressLint("ClickableViewAccessibility")
@Override
public boolean onTouch(@Nullable View view, @NonNull MotionEvent arg1) {
if (view == null)
return false;
if (!view.hasFocus()) {
view.requestFocus();
}
mAction = arg1.getAction();
mY = arg1.getY();
if (mAction == MotionEvent.ACTION_DOWN) {
mLocation = mY;
} else if (mAction == MotionEvent.ACTION_UP) {
final float distance = (mY - mLocation);
if (distance > SCROLL_UP_THRESHOLD && view.getScrollY() < SCROLL_UP_THRESHOLD) {
mUIController.showActionBar();
} else if (distance < -SCROLL_UP_THRESHOLD) {
mUIController.hideActionBar();
}
mLocation = 0;
}
mGestureDetector.onTouchEvent(arg1);
return false;
}
/**
* We only want the current page that is being shown to be focusable.
*/
@Override
protected boolean onRequestFocusInDescendants(int direction,
Rect previouslyFocusedRect) {
int index;
int increment;
int end;
int count = getChildCount();
if ((direction & FOCUS_FORWARD) != 0) {
index = 0;
increment = 1;
end = count;
} else {
index = count - 1;
increment = -1;
end = -1;
}
for (int i = index; i != end; i += increment) {
View child = getChildAt(i);
if (child.getVisibility() == VISIBLE) {
ItemInfo ii = infoForChild(child);
if (ii != null && ii.position == mCurItem) {
if (child.requestFocus(direction, previouslyFocusedRect)) {
return true;
}
}
}
}
return false;
}
void moveToCustomContentScreen(boolean animate) {
if (hasCustomContent()) {
int ccIndex = getPageIndexForScreenId(CUSTOM_CONTENT_SCREEN_ID);
if (animate) {
snapToPage(ccIndex);
} else {
setCurrentPage(ccIndex);
}
View child = getChildAt(ccIndex);
if (child != null) {
child.requestFocus();
}
}
exitWidgetResizeMode();
}
/**
* We only want the current page that is being shown to be focusable.
*/
@Override
protected boolean onRequestFocusInDescendants(int direction,
Rect previouslyFocusedRect) {
int index;
int increment;
int end;
int count = getChildCount();
if ((direction & FOCUS_FORWARD) != 0) {
index = 0;
increment = 1;
end = count;
} else {
index = count - 1;
increment = -1;
end = -1;
}
for (int i = index; i != end; i += increment) {
View child = getChildAt(i);
if (child.getVisibility() == VISIBLE) {
ItemInfo ii = infoForChild(child);
if (ii != null && ii.position == mCurItem) {
if (child.requestFocus(direction, previouslyFocusedRect)) {
return true;
}
}
}
}
return false;
}
private boolean scrollAndFocusH(int direction, int left, int right) {
boolean handled = true;
int width = getWidth();
int containerLeft = getScrollX();
int containerRight = containerLeft + width;
boolean goLeft = direction == View.FOCUS_LEFT;
View newFocused = findFocusableViewInBoundsH(goLeft, left, right);
if (newFocused == null) {
newFocused = this;
}
if (left >= containerLeft && right <= containerRight) {
handled = false;
} else {
int delta = goLeft ? (left - containerLeft)
: (right - containerRight);
doScrollX(delta);
}
if (newFocused != findFocus() && newFocused.requestFocus(direction)) {
mScrollViewMovedFocus = true;
mScrollViewMovedFocus = false;
}
return handled;
}
/**
* Fling the scroll view
*
* @param velocityY The initial velocity in the Y direction. Positive
* numbers mean that the finger/curor is moving down the screen,
* which means we want to scroll towards the top.
*/
public void fling(int velocityX, int velocityY) {
if (getChildCount() > 0) {
int height = getHeight() - getPaddingBottom() - getPaddingTop();
int bottom = getChildAt(0).getHeight();
int width = getWidth() - getPaddingRight() - getPaddingLeft();
int right = getChildAt(0).getWidth();
mScroller.fling(getScrollX(), getScrollY(), velocityX, velocityY, 0, right - width, 0, bottom - height);
final boolean movingDown = velocityY > 0;
final boolean movingRight = velocityX > 0;
View newFocused = findFocusableViewInMyBounds(movingRight, mScroller.getFinalX(), movingDown, mScroller.getFinalY(), findFocus());
if (newFocused == null) {
newFocused = this;
}
if (newFocused != findFocus() && newFocused.requestFocus(movingDown ? View.FOCUS_DOWN : View.FOCUS_UP)) {
mTwoDScrollViewMovedFocus = true;
mTwoDScrollViewMovedFocus = false;
}
awakenScrollBars(mScroller.getDuration());
invalidate();
}
}
public void setViewFocus(View view) {
if (view != null) {
view.setFocusable(true);
view.setFocusableInTouchMode(true);
view.requestFocus();
view.requestFocusFromTouch();
}
}
/**
* Request natural focus.
*
* @param direction direction in which focus is changing
* @param previouslyFocusedRect previously focus rectangle
*/
private void requestNaturalFocus(int direction, Rect previouslyFocusedRect) {
FocusFinder ff = FocusFinder.getInstance();
previouslyFocusedRect = previouslyFocusedRect == null
? new Rect(0, 0, 0, 0) : previouslyFocusedRect;
View toFocus = ff.findNextFocusFromRect(this, previouslyFocusedRect, direction);
toFocus = toFocus == null ? getChildAt(0) : toFocus;
if (toFocus != null) {
toFocus.requestFocus();
}
}
/**
* We only want the current page that is being shown to be focusable.
*/
@Override
protected boolean onRequestFocusInDescendants(int direction,
Rect previouslyFocusedRect) {
int index;
int increment;
int end;
int count = getChildCount();
if ((direction & FOCUS_FORWARD) != 0) {
index = 0;
increment = 1;
end = count;
} else {
index = count - 1;
increment = -1;
end = -1;
}
for (int i = index; i != end; i += increment) {
View child = getChildAt(i);
if (child.getVisibility() == VISIBLE) {
ItemInfo ii = infoForChild(child);
if (ii != null && ii.position == mCurItem) {
if (child.requestFocus(direction, previouslyFocusedRect)) {
return true;
}
}
}
}
return false;
}
public boolean arrowScroll(int direction) {
View currentFocused = findFocus();
if (currentFocused == this) currentFocused = null;
boolean handled = false;
View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused,
direction);
if (nextFocused != null && nextFocused != currentFocused) {
if (direction == View.FOCUS_LEFT) {
handled = nextFocused.requestFocus();
} else if (direction == View.FOCUS_RIGHT) {
// If there is nothing to the right, or this is causing us to
// jump to the left, then what we really want to do is page right.
if (currentFocused != null && nextFocused.getLeft() <= currentFocused.getLeft()) {
handled = pageRight();
} else {
handled = nextFocused.requestFocus();
}
}
} else if (direction == FOCUS_LEFT || direction == FOCUS_BACKWARD) {
// Trying to move left and nothing there; try to page.
handled = pageLeft();
} else if (direction == FOCUS_RIGHT || direction == FOCUS_FORWARD) {
// Trying to move right and nothing there; try to page.
handled = pageRight();
}
if (handled) {
playSoundEffect(SoundEffectConstants.getContantForFocusDirection(direction));
}
return handled;
}
@Override
protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) {
View topView = AbstractFloatingView.getTopOpenView(mLauncher);
if (topView != null) {
return topView.requestFocus(direction, previouslyFocusedRect);
} else {
return super.onRequestFocusInDescendants(direction, previouslyFocusedRect);
}
}
@Override
public void run(Boolean focus, View view) {
if (view == null)
return;
if (focus) {
view.setFocusable(true);
view.requestFocus();
}
else {
view.clearFocus();
view.setFocusable(false);
}
}
private void requestFocus(View view) {
if (view.requestFocus()) {
getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
}
}
@Override
public boolean onTouch(View v, MotionEvent event) {
v.getParent().requestDisallowInterceptTouchEvent(true);
if(!isInside(event)) {
switch (event.getAction()) {
case MotionEvent.ACTION_UP:
if (mTouched) {
v.requestFocus();
v.requestFocusFromTouch();
if (mClickListener != null) {
mClickListener.onClick(v);
}
}
v.setPressed(false);
mTouched = false;
}
return true;
} else {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
v.setPressed(true);
mTouched = true;
return true;
case MotionEvent.ACTION_UP:
if (mTouched && ViewUtils.isInsideView(v, (int)event.getRawX(), (int)event.getRawY())) {
v.requestFocus();
v.requestFocusFromTouch();
if (mClickListener != null) {
mClickListener.onClick(v);
}
}
v.setPressed(false);
mTouched = false;
return true;
case MotionEvent.ACTION_MOVE:
return true;
case MotionEvent.ACTION_CANCEL:
v.setPressed(false);
mTouched = false;
return true;
}
return false;
}
}
/**
* 初始化控件
*/
private void initView()
{
mVPip = LayoutInflater.from(getApplicationContext()).inflate(R.layout.view_pip, null);
View rlPip = (RelativeLayout) mVPip.findViewById(R.id.rl_pip);
mFmPip = (FrameLayout) rlPip.findViewById(R.id.fm_pip);
mLnFrameBg = (LinearLayout) rlPip.findViewById(R.id.ln_bg);
mPgbLoading = (ProgressBar) mFmPip.findViewById(R.id.pgb_loading);
mRlFrame = (RelativeLayout) mFmPip.findViewById(R.id.rl_frame);
mTvNoSingle = (TextView) mFmPip.findViewById(R.id.tv_no_single);
mRlController = (RelativeLayout) mVPip.findViewById(R.id.rl_control);
mLnController = (LinearLayout) mRlController.findViewById(R.id.ln_controller);
mLnScale = (LinearLayout) mRlController.findViewById(R.id.ln_scale);
mLnAudio = (LinearLayout) mRlController.findViewById(R.id.ln_audio);
mImgSwitch = (ImageView) mLnAudio.findViewById(R.id.img_switch);
mTvReminds = (TextView) mRlController.findViewById(R.id.tv_reminds);
mSfPip = (SurfaceView) mFmPip.findViewById(R.id.sf_pip);
SurfaceHolder holder = mSfPip.getHolder();
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
holder.addCallback(this);
View move = mLnController.findViewById(R.id.tv_move);
mTvScale = (TextView) mLnController.findViewById(R.id.tv_scale);
mTvAudio = (TextView) mLnController.findViewById(R.id.tv_audio);
View exit = mLnController.findViewById(R.id.tv_exit);
View audioSwitch = mLnAudio.findViewById(R.id.rl_audio);
mScales = new TextView[4];
mScales[0] = mLnScale.findViewById(R.id.tv_scale_0);
mScales[1] = mLnScale.findViewById(R.id.tv_scale_1);
mScales[2] = mLnScale.findViewById(R.id.tv_scale_2);
mScales[3] = mLnScale.findViewById(R.id.tv_scale_3);
for (int i = 0; i < mScales.length; i++)
{
View v = mScales[i];
v.setTag(i);
v.setOnClickListener(this);
v.setOnKeyListener(this);
v.setOnFocusChangeListener(this);
}
mScales[mScaleMode].setSelected(true);
move.setOnClickListener(this);
mTvScale.setOnClickListener(this);
mTvAudio.setOnClickListener(this);
exit.setOnClickListener(this);
audioSwitch.setOnClickListener(this);
move.setOnFocusChangeListener(this);
mTvScale.setOnFocusChangeListener(this);
mTvAudio.setOnFocusChangeListener(this);
exit.setOnFocusChangeListener(this);
audioSwitch.setOnFocusChangeListener(this);
move.setOnKeyListener(this);
mTvScale.setOnKeyListener(this);
mTvAudio.setOnKeyListener(this);
exit.setOnKeyListener(this);
audioSwitch.setOnKeyListener(this);
mFmPip.setOnKeyListener(this);
adjustPipFrame(mWindowType.x, mWindowType.y, mWindowType.width, mWindowType.height);
WindowManager.LayoutParams params = new WindowManager.LayoutParams();
params.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
params.format = PixelFormat.RGBA_8888; // 设置图片格式，效果为背景透明
params.flags = WindowManager.LayoutParams.FLAG_FULLSCREEN;
params.width = WindowManager.LayoutParams.MATCH_PARENT;
params.height = WindowManager.LayoutParams.MATCH_PARENT;
((WindowManager) getSystemService(WINDOW_SERVICE)).addView(mVPip, params);
move.requestFocus();
}