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Android

textview带有右上角文字

rightuptext pic

1.RightUpperCornerText 代码

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public class RightUpperCornerText extends TextView {
    private Paint mPaint;
    private String mCornerText;
    private Context mContext;
    public RightUpperCornerText(Context context) {
        super(context);
        init(context);
    }
    public RightUpperCornerText(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }
    public RightUpperCornerText(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context);
    }
    private void init(Context context) {
        mContext = context;
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setColor(Color.WHITE);
        float cornerSize = getTextSize() * 0.6f;
        if (cornerSize > 50) {
            cornerSize = 50;
        }
        mPaint.setTextSize(cornerSize);
        mCornerText = "";
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        // 不要忘了设置 Padding
        String text = (String) getText();
        Rect bounds = new Rect();
        getPaint().getTextBounds(text, 0, text.length(), bounds);
        canvas.drawText(mCornerText, getPaddingLeft() + bounds.right + bounds.left,
                (canvas.getHeight() + bounds.top) / 2 + mPaint.measureText(mCornerText),
                mPaint);
    }
    public void setCornertext(String text) {
        mCornerText = text;
    }
    public void setCornertextSize(float size) {
        mPaint.setTextSize(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
                size, mContext.getResources().getDisplayMetrics()));
        invalidate();
    }
}

2. 用法

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<com.ilegendsoft.toprankapps.cleanmaster.UI.RightUpperCornerText
    android:id="@+id/dashboard_percentage"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:padding="20dp"
    android:layout_centerInParent="true"
    android:textColor="@android:color/white"
    android:textSize="26sp" />

mPercentageView.setCornertext(cornerText);

注意 android:padding="20dp"设置padding 很重要，否则没地方画了。

3. 其实完全没必要自定义，采用TextView Style可以实现各种样式的字体排版，就是SpannableString

先看下图片

复合文本图片

具体参考如下链接：

Android

listview item进入和删除动画

1.先看一下最终效果

listview

2.从右边划入的动画

  • 定义xml动画
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<?xml version="1.0" encoding="utf-8"?>
<translate xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="@integer/animTime"
    android:fromXDelta="100%p"
    android:toXDelta="0%p" >
</translate>
  • Adapter里只需要写如下代码
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@Override
public View getChildView(final int groupPosition, int childPosition, 
     boolean isLastChild, View convertView, ViewGroup parent) {
    ....
    if (!junk.isAnimatedBefore()) {
        junk.setAnimatedBefore(true);
        convertView.startAnimation(AnimationUtils.loadAnimation(mContext, R.anim.slide_left_in));
    }else{
        convertView.clearAnimation();
    }
    return convertView;
}

3.从左边划出的动画

  • 定义xml动画
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<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:fillEnabled="true"
    android:fillAfter="true"
    android:duration="@integer/animTime">
    <translate
        android:fromXDelta="0%p"
        android:toXDelta="-100%p">
    </translate>
</set>
  • Adapter里不需要做什么，需要在外面操作ListView.

4.在外面操作ListView

  • 开始动画
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private void startBoost() {
    mIsDeleting = true;
    boolean hasAnimation = false;
    long offset = 0;
    mAnimCount = 0;
    int groupPosition = -1;
    int childPosition = -1;
    Iterator<ArrayList<Junk>> listIterator = mChildren.iterator();
    while (listIterator.hasNext()) {
        groupPosition++;
        final Iterator<Junk> junkIterator = listIterator.next().iterator();
        while (junkIterator.hasNext()) {
            childPosition++;
            Junk junk = junkIterator.next();
            if (junk.isChecked()) {
                ...
                junkIterator.remove();
                final View itemView = ListViewUtil.getChildItemView(this,
                                                 mListView, groupPosition, childPosition);
                if (itemView != null) {
                    hasAnimation = true;
                    ((Animation) itemView.getTag(R.id.anim)).setAnimationListener(mAnimationListener);
                    ((Animation) itemView.getTag(R.id.anim)).setStartOffset(offset);
                    offset += 100;
                    itemView.startAnimation(((Animation) itemView.getTag(R.id.anim)));
                }
            }
        }
    }
    if (!hasAnimation) {
        deleteCompleted();
    }
}
  • mAnimationListener定义如下：
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private Animation.AnimationListener mAnimationListener = new Animation.AnimationListener() {
    @Override
    public void onAnimationStart(Animation animation) {
        mAnimCount++;
    }
    @Override
    public void onAnimationEnd(Animation animation) {
        mAnimCount--;
        if (mAnimCount == 0) {
            deleteCompleted();
        }
    }
    @Override
    public void onAnimationRepeat(Animation animation) {
    }
};
  • 删除完成后需要调用ListViewUtil.clearListViewAnim(this, mListView);,否则原来动画的地方会显示空白。
  • 动画时要禁用OnTouch事件，因为我们做动画时并没有调用mAdapter.notifyDataSetChanged()，所以如果滚动，由于数据没有同步，肯定会挂掉。

禁用OnTouch事件的方法如下

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@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
    // intercept touch event when deleting ,avoid listview get view.
    if (mIsDeleting) {
        return true;
    }
    return super.dispatchTouchEvent(ev);
}

4.ListView的工具方法

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public static View getChildItemView(Context context, FloatingGroupExpandableListView listView, int groupPosition, int childPosition) {
    long packedPosition = ExpandableListView.getPackedPositionForChild(groupPosition, childPosition);
    int flatPosition;
    try {
        flatPosition = listView.getFlatListPosition(packedPosition);
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
    int firstPosition = listView.getFirstVisiblePosition();
    int wantedChild = flatPosition - firstPosition;
    if (wantedChild < 0 || wantedChild >= listView.getChildCount()) {
        return null;
    }
    View childItemView = listView.getChildAt(wantedChild);
    childItemView.setTag(R.id.anim, AnimationUtils.loadAnimation(context, R.anim.slide_left_out));
    return childItemView;
}
public static View getItemView(Context context, ListView listView, int position) {
    int firstPosition = listView.getFirstVisiblePosition() - listView.getHeaderViewsCount();
    int wantedChild = position - firstPosition;
    if (wantedChild < 0 || wantedChild >= listView.getChildCount()) {
        return null;
    }
    View wantedView = listView.getChildAt(wantedChild);
    wantedView.setTag(R.id.anim, AnimationUtils.loadAnimation(context, R.anim.slide_left_out));
    return wantedView;
}
public static void clearListViewAnim(Context context, ListView listView) {
    int first = listView.getFirstVisiblePosition();
    int count = listView.getChildCount() + 2;
    for (int i = first; i < first + count; i++) {
        View itemView = getItemView(context, listView, i);
        if (itemView != null) {
            itemView.clearAnimation();
        }
    }
}
Android

如何确保Listview刷新结束,然后再执行其他操作。

场景：当调用Listview 的notifyDataSetChanged()刷新列表时，执行滚动或点击按钮删除源数据，然后再次刷新列表。

方法：采用View的post()方法,把对数据源的操作加入消息队列，等待刷新结束，如下：

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adapter.notifyDataSetChanged();
view.post( new Runnable() {
    @Override
    public void run() {
    //call smooth scroll
    }
  });