第一次写文章,多多包涵。别的不多说,直接看效果
仿照的
顶部的搜索+选中时显示的头像,通过自定义ViewGroup,RecycleView+EditText。
通过onMeasure测量,当EditText的长度小于指定的最小长度时,对RecycleView 的长度固定
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int count = getChildCount();
for (int i = 0; i < count; i++) {
View view = getChildAt(i);
if (view instanceof ViewGroup) {
childMeasure((ViewGroup) view);
}
}
}
private void childMeasure(ViewGroup viewGroup) {
int childCount = viewGroup.getChildCount();
for (int j = 0; j < childCount; j++) {
View child = viewGroup.getChildAt(j);
if (child == scRecycler) {
//如果子view 是RecycleView
int rootWidth = getMeasuredWidth(); //根View的长度
int width = scRecycler.getMeasuredWidth(); //当前RecycleView的长度
if (rootWidth - width < searchMinWidth) { //如果小于EditText指定的最小宽度
setMeasureChildSpec(rootWidth - searchMinWidth, scRecycler.getMeasuredHeight(), scRecycler);
setMeasureChildSpec(searchMinWidth, scEditQuery.getMeasuredHeight(), scEditQuery);
}
break;
} else {
if (child instanceof ViewGroup) {
childMeasure((ViewGroup) child);
break;
}
}
}
}
private void setMeasureChildSpec(int width, int height, View view) {
int measuredWidthSpec = MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY);
int measuredHeightSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
view.measure(measuredWidthSpec, measuredHeightSpec);
}
搜索icon是通过监听 RecycleView.AdapterDataObserver的变化实现显示和隐藏
private final RecyclerView.AdapterDataObserver adapterDataObserver = new RecyclerView.AdapterDataObserver() {
private void update() {
if (scRecycler != null && scRecycler.getAdapter() != null) {
boolean isShow = true;
if (scRecycler.getAdapter().getItemCount() == 0) {
isShow = true;
scRecycler.setVisibility(GONE);
} else {
isShow = false;
scRecycler.setVisibility(VISIBLE);
scRecycler.scrollToPosition(scRecycler.getAdapter().getItemCount() - 1);
}
updateSearchIcon(isShow);
}
}
@Override
public void onChanged() {
super.onChanged();
update();
}
@Override
public void onItemRangeChanged(int positionStart, int itemCount) {
super.onItemRangeChanged(positionStart, itemCount);
update();
}
@Override
public void onItemRangeInserted(int positionStart, int itemCount) {
super.onItemRangeInserted(positionStart, itemCount);
update();
}
@Override
public void onItemRangeMoved(int fromPosition, int toPosition, int itemCount) {
super.onItemRangeMoved(fromPosition, toPosition, itemCount);
update();
}
@Override
public void onItemRangeRemoved(int positionStart, int itemCount) {
super.onItemRangeRemoved(positionStart, itemCount);
update();
}
};
第一次点击返回键头像颜色变浅,是通过Drawable tint着色实现的
ImageView image = holder.findViewById(R.id.img_head);
Drawable drawable = image.getDrawable();
Drawable tintDrawable = DrawableCompat.wrap(drawable.getConstantState() == null ?
drawable : drawable.getConstantState().newDrawable()).mutate();
DrawableCompat.setTintMode(tintDrawable, PorterDuff.Mode.SCREEN);
DrawableCompat.setTint(tintDrawable, Color.parseColor("#D9D9D9"));
image.setImageDrawable(tintDrawable);
需要注意 Drawable mutate,由于Android为了优化系统性能,同一个Drawable实例只会存一份在内存中,如果对Drawable进行修改,会导致全局的同一Drawable进行修改
不使用mutate 共享模式
使用mutate 不共享模式