基于Android的浮动组件，可以用于应用中的新功能展示

/** * */ package com.flysnow.widget; import android.content.Context; import android.graphics.Color; import android.graphics.Rect; import android.os.Handler; import android.os.HandlerThread; import android.os.Looper; import android.os.Message; import android.text.TextPaint; import android.util.TypedValue; import android.view.Gravity; import android.view.View; import android.widget.TextView; import android.widget.Toast; /** * 浮动的文本显示。根据一个提供的View，可以把文本显示到该View的下面. * 可以设置显示的时间，多了该时间后自动消失。目前只支持纯文本{@link String}类型的显示 * 因为要计算显示文本的宽度。 * @author michael_li(飞雪无情) * @since 2011-12-10 下午04:57:36 */ public class FloatTextToast { public static final int LENGTH_LONG=Toast.LENGTH_LONG; public static final int LENGTH_SHORT=Toast.LENGTH_SHORT; private static final int WHAT_SHOW=1; private Context mContext; private View mTargetView; private Toast mToast; private TextView mContentView; private HandlerThread mHandlerThread; private FloatTextToastHandler mHandler; private FloatTextToast(Context context,View targetView) { this.mTargetView = targetView; this.mContext= context; mToast=new Toast(mContext); mContentView=new TextView(mContext); mContentView.setBackgroundResource(R.drawable.float_text_toast_bg); mContentView.setTextColor(Color.BLACK); mContentView.setTextSize(TypedValue.COMPLEX_UNIT_DIP,16); mToast.setView(mContentView); //初始化一个Handler线程 mHandlerThread=new HandlerThread("FloatTextToast"); mHandlerThread.start(); mHandler=new FloatTextToastHandler(mHandlerThread.getLooper()); } /** * 生成一个FloatTextToast * @param context Activity 上下文 * @param targetView 目标View，浮动文本要显示在哪个View下面 * @param text 要显示的文本 * @param duration 浮动文本显示的时间 {@link #LENGTH_LONG} {@link #LENGTH_SHORT} * @return 一个FloatTextToast，可以调用{@link #show()}显示 */ public static FloatTextToast makeText(Context context,View targetView, String text, int duration) { final FloatTextToast floatToast=new FloatTextToast(context,targetView); final TextView contentView=floatToast.mContentView; contentView.setText(text); floatToast.mToast.setDuration(duration); return floatToast; } /** * 显示浮动文本 */ public void show(){ mHandler.sendEmptyMessage(WHAT_SHOW); } /**在Handler调用的show方法，主要为了等待{@link #mTargetView}的位置*/ private void showInHandler(){ int[] targetPos=getTargetViewPos(); if(targetPos[0]==0&&targetPos[1]==0){ mHandler.sendEmptyMessageDelayed(WHAT_SHOW, 100); }else{ final Rect contentPos=getContentViewPos(targetPos); mToast.setGravity(Gravity.LEFT|Gravity.TOP, contentPos.left, contentPos.top); mToast.show(); } } private int[] getTargetViewPos(){ final int[] targetPos=new int[2]; mTargetView.getLocationInWindow(targetPos); return targetPos; } /** * 计算获取浮动文本显示的位置，把浮动文本放在targetView的中心处 * @return 一个包含top和left的Rect */ private Rect getContentViewPos(int[] targetPos){ final Rect windowVisibleRect=new Rect(); final View targetView=mTargetView; final TextView contentView=mContentView; //状态栏高度 targetView.getWindowVisibleDisplayFrame(windowVisibleRect); int statusBarHeight=windowVisibleRect.top; //背景图那个三角箭头的位置 final TextPaint textPaint=contentView.getPaint(); int contentW=(int)textPaint.measureText((String)contentView.getText()); int arrowPos=(int)(contentW*(30.0/160)); final Rect rect = new Rect(); rect.left = targetPos[0]+targetView.getWidth()/2-arrowPos; rect.top = targetPos[1]-statusBarHeight + targetView.getHeight(); return rect; } private class FloatTextToastHandler extends Handler{ public FloatTextToastHandler(Looper looper) { super(looper); } @Override public void handleMessage(Message msg) { switch(msg.what){ case WHAT_SHOW: showInHandler(); } } } }