基于Android 13,Launcher3实现需求：
1. 长按Hotseat的图标显示红色删除角标
2. 点击角标，删除图标并保存到Database
3.点击其他地方，取消编辑hotseat图标模式
实现效果：
实现原理：
图标是由BubbleTextView来是实现的，是一个TextView，要增加角标应该有几种思路：
1.TextView可以设置 left top bottom right 4个drawable，top已经用作实际的icon，这个应该布局不了
2. 修改背景background,在适当的时候修改background？
3.重写TextView的onDraw,适当的时候在原来的基础上画出额外的角标
查看Android13原生的Launcher代码发现 BubbleTextView的onDraw已经有DotRenderer的实现，显示的应该是应用通知，因此模仿这个实现思路即可。
查看源码发现实际使用的是DoubleShadowBubbleTextView.java，调用到的是ondraw调用的是drawWithoutDot
因此在BubbleTextView.java中添加代码即可实现：
protected void drawWithoutDot(Canvas canvas) {
super.onDraw(canvas);
drawMyDotIfNecessary(canvas);
}
protected void drawMyDotIfNecessary(Canvas canvas){
if(!mIsDeleteHidden) {
Paint paint = new Paint();
paint.setColor(Color.RED); // 角标颜色
paint.setStyle(Paint.Style.FILL);
canvas.drawCircle(getWidth() - 30f, 30f, 30f, paint);
}
}
接下来应该需要实现在什么时候显示圆点操作，
比方说长按某一个hotseat里图标，则所有的view都添加这个圆点
长按图标事件可以得到，在什么时候取消呢？点击图标非圆点处取消。
接下来实现，点击圆点事件：把点击事件传到mHotseatController里删除并更新hotseat里的view
step1: 在BubbleTextView.java里实现onDraw画图，捕捉点击圆点事件，实现显示隐藏角标接口
private boolean mIsDeleteHidden = true;//Kevin.Ye added
private boolean mIsDownInDotErea = false;//
private Rect mRectDotBounds = null;//
private OnDotClkListener mOnDotClkListener = null;
//Kevin.Ye added end
@Override
public boolean onTouchEvent(MotionEvent event) {
// ignore events if they happen in padding area
if(cancelDotIfNecessary(event))//added by Kevin.Ye case when Dot is shown
return true;//end
if (event.getAction() == MotionEvent.ACTION_DOWN
&& shouldIgnoreTouchDown(event.getX(), event.getY())) {
return false;
}
if (isLongClickable()) {
super.onTouchEvent(event);
mLongPressHelper.onTouchEvent(event);
// Keep receiving the rest of the events
return true;
} else {
return super.onTouchEvent(event);
}
}
private boolean cancelDotIfNecessary(MotionEvent event){
if(isMyDotHidden())
return false;
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
if(isTouchInDotErea((int)event.getX(),(int)event.getY())) {
mIsDownInDotErea = true;
return true;
}
break;
case MotionEvent.ACTION_UP:
if(mIsDownInDotErea){
mIsDownInDotErea = false;
if(isTouchInDotErea((int)event.getX(),(int)event.getY())){
onClkMyDot();
return true;
}else{
Log.d("dot","touch up elsewhere");
}
}
break;
}
return false;
}
private boolean isTouchInDotErea(int x,int y){
Log.d("dot","touch x:"+x+" y:"+y);
if(mRectDotBounds == null) {
mRectDotBounds = new Rect(getWidth() - 60, 0, getWidth(), 60);
}
return mRectDotBounds.contains(x,y);
}
private void onClkMyDot(){
Log.d("dot","onClkMyDot");
if(mOnDotClkListener != null)
mOnDotClkListener.onClkIconDot(BubbleTextView.this);
}
public interface OnDotClkListener{
void onClkIconDot(View view);
}
public void setOnDotClkListener(OnDotClkListener onDotClkListener){
mOnDotClkListener = onDotClkListener;
}
/*
*draw my dot for deleting or added icon Kevin.Ye
*/
private boolean isMyDotHidden(){
return mIsDeleteHidden;
}
public void setDeleteDotHidden(boolean hide){
mIsDeleteHidden = hide;
invalidate();
}
protected void drawMyDotIfNecessary(Canvas canvas){
if(!mIsDeleteHidden) {
Paint paint = new Paint();
paint.setColor(Color.RED); // 角标颜色 paint.setStyle(Paint.Style.FILL);
canvas.drawCircle(getWidth() - 30f, 30f, 30f, paint);
}
}
step2： HotseatController.java（注意本类是源码没有的），实现显示角标、取消显示角标、响应删除图标三个接口
private boolean mIsInDeletingMode = false;
public boolean isInDeletingMode(){
return mIsInDeletingMode;
}
public void showHotseatDeleteDot(){
mIsInDeletingMode = true;
Hotseat hs = mLauncher.getHotseat();
int gridCount = getGridCount(mLauncher);
//ArrayList<View> views = new ArrayList<>();
for (int i = 0; i < gridCount; i++) {
int cx = hs.getCellXFromOrder(i);
int cy = hs.getCellYFromOrder(i);
View v = hs.getShortcutsAndWidgets().getChildAt(cx, cy);
if (hs.isOccupied(cx, cy)) {
if (v != null) {
if(v instanceof BubbleTextView){
Log.d("dot","v instanceof BubbleTextView!!!");
((BubbleTextView)v).setDeleteDotHidden(false);
((BubbleTextView)v).setOnDotClkListener(mOnDotClkListener);
}
}
}
}
}
public void cancelDeletingMode(){
mIsInDeletingMode = false;
Hotseat hs = mLauncher.getHotseat();
int gridCount = getGridCount(mLauncher);
//ArrayList<View> views = new ArrayList<>();
for (int i = 0; i < gridCount; i++) {
int cx = hs.getCellXFromOrder(i);
int cy = hs.getCellYFromOrder(i);
View v = hs.getShortcutsAndWidgets().getChildAt(cx, cy);
if (hs.isOccupied(cx, cy)) {
if (v != null) {
if(v instanceof BubbleTextView){
Log.d("dot","v instanceof BubbleTextView!!!");
((BubbleTextView)v).setDeleteDotHidden(true);
}
}
}
}
}
BubbleTextView.OnDotClkListener mOnDotClkListener = new BubbleTextView.OnDotClkListener() {
@Override
public void onClkIconDot(View view) {
Log.d("dot","HotseatController onClkMyDot");
Hotseat hs = mLauncher.getHotseat();
hs.removeView(view);
//Log.d("dot","view.getTag() :"+view.getTag().toString());
Object tag = view.getTag();
WorkspaceItemInfo info = tag instanceof WorkspaceItemInfo ? (WorkspaceItemInfo) tag : null;
if(info != null) {
mLauncher.getModelWriter().deleteItemFromDatabase(info,null);
}
}
};step3:Launcher.java中增加调用取消编辑hotseat模式（隐藏角标）
private HotseatController mHotseatController = null;//Kevin.Ye
mHotseatController = new HotseatController(this.getApplicationContext(),this);//Kevin.Ye
/**
*Return HotseatController Kevin.Ye added
*/
public HotseatController getHotseatController(){
return mHotseatController;
}
@Override
public boolean startActivitySafely(View v, Intent intent, ItemInfo item) {
/*Kevin.Ye added for cancel deleting mode*/
if(getHotseatController().isInDeletingMode()){
getHotseatController().cancelDeletingMode();
return true;
}
}
step4:src/com/android/launcher3/Workspace.java 中的接口DragView beginDragShared
实现长按进入Hotseat图标编辑模式（显示删除角标）
if (child.getParent() instanceof ShortcutAndWidgetContainer) {
mDragSourceInternal = (ShortcutAndWidgetContainer) child.getParent();
}
if (child instanceof BubbleTextView && !dragOptions.isAccessibleDrag) {
//Kevin.Ye added for showing hotseat edit mode
boolean bStartLongPressAction = true;
if(child.getParent() instanceof ShortcutAndWidgetContainer)
if(child.getParent().getParent() instanceof Hotseat){
mLauncher.getHotseatController().showHotseatDeleteDot();
bStartLongPressAction = false;
}
//add end
if(bStartLongPressAction)
dragOptions.preDragCondition = ((BubbleTextView) child).startLongPressAction();
}后续应该用加载drawable的方式来代替drawCircle画图，删除图标后应该重新排布热座上的图标。
