android闪动的文字和文字进度条控件（带源码）

以前看到过有进度条是填充文字的，好奇心作祟，便想自己写一个试试，但是还是比较粗糙，进度条末端没有水流等涌动的效果。

两个控件都是继承TextView，便于设置字体大小等相关属性。

1，GradientTextView  渐变颜色的文字控件

主要用到LinearGradient类，用于渐变颜色，

new LinearGradient(0, 0, width, height, colorArrays[colorIndex], gradientSpread, Shader.TileMode.MIRROR);

参数对应如下，

参数1，参数2：渐变色起点位置。

参数3，参数4：渐变色终点位置。

参数5：渐变色的渐变颜色数组

参数6：渐变色的分布数组（需要和参数5中数组长度相同）

参数7：着色器模式

例子中定时替换渐变色数组colorArrays来达到文字颜色闪动的效果。

 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.LinearGradient;
 import android.graphics.Paint;
 import android.graphics.Shader;
 import android.os.Handler;
 import android.os.Message;
 import android.util.AttributeSet;
 import android.widget.TextView;

 /**
  * @author jayce
  * @date 2015/1/23
  */
 public class GradientTextView extends TextView {
     private int[] colorArray1 = new int[]{Color.RED, Color.GREEN, Color.BLUE};
     private int[] colorArray2 = new int[]{Color.GREEN, Color.BLUE, Color.RED};
     private int[] colorArray3 = new int[]{Color.BLUE, Color.RED, Color.GREEN};

     private int[][] colorArrays = new int[][]{colorArray1, colorArray2, colorArray3};
     private int colorIndex = 0;
     private float[] gradientSpread = new float[]{0, 0.5f, 1.0f};

     private static final int COLORINVALIDATE=0;

     private int width;
     private int height;

     private Handler handler = new Handler() {
         @Override
         public void handleMessage(Message msg) {
             super.handleMessage(msg);

             colorIndex = (colorIndex + 1) % 3;
             invalidate();
         }
     };

     public GradientTextView(Context context) {
         this(context, null);
     }

     public GradientTextView(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public GradientTextView(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
         width = getMeasuredWidth();
         height = getMeasuredHeight();
     }



     @Override
     protected void onDraw(Canvas canvas) {
         //super.onDraw(canvas);
         Paint paint = getPaint();
         paint.setAntiAlias(true);
         LinearGradient lg = new LinearGradient(0, 0, width, height, colorArrays[colorIndex], gradientSpread, Shader.TileMode.MIRROR);
         paint.setShader(lg);

         canvas.drawText(getText().toString(), 0, height, paint);
         handler.sendEmptyMessageDelayed(COLORINVALIDATE,500);
     }
 }

2，GradientTextViewProgress
在onDraw()中drawText，注意drawText中 canvas.drawText(getText().toString(), 0, baseline, paint);
参数3是baseline的高度。
先用背景画笔画出背景文字，然后用另外一个画笔画出进度，调用canvas.clipRect来裁剪。每次设置进度后，刷新控件。

 package huwei.com.gradienttextviewdemo;

 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.LinearGradient;
 import android.graphics.Paint;
 import android.graphics.Rect;
 import android.graphics.Shader;
 import android.util.AttributeSet;
 import android.view.View;
 import android.widget.TextView;

 /**
  * @author jayce
  * @date 2015/1/23
  */
 public class GradientTextProgress extends TextView {
     private String mText;
     private int maxValue;
     private int curValue;
     private Paint bgPaint,paint;//<»­±Ê
     private int mWidth, mHeight, baseline;
     private int bgColorInt=Color.BLACK;
     private int proColorInt=Color.BLUE;

     private LinearGradient lg;  //½¥±äÉ«
     private boolean hasGradient;
     private int[] color;
     private float[] position;
     private Shader.TileMode mode;

     public GradientTextProgress(Context context) {
         this(context, null);
     }

     public GradientTextProgress(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public GradientTextProgress(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);

         initPaint();

         mText = getText().toString();
     }

     private void initPaint() {
         bgPaint = getPaint();
         bgPaint.setAntiAlias(true);
         bgPaint.setTextSize(getTextSize());

         paint=new Paint();
         paint.set(bgPaint);
     }

     public int getMaxValue() {
         return maxValue;
     }

     public void setMaxValue(int maxValue) {
         this.maxValue = maxValue;
     }

     public String getmText() {
         return mText;
     }

     public void setmText(String mText) {
         this.mText = mText;
         invalidate();
     }

     public int getProgress() {
         return curValue;
     }

     public void setLinearGradient(int color[],float position[],Shader.TileMode mode) {
         hasGradient=true;
         this.color=color;
         this.position=position;
         this.mode=mode;
     }

     public void setProgress(int curValue) {
         this.curValue = curValue;
         invalidate();
     }

     public int getBgColorInt() {
         return bgColorInt;
     }

     //ÉèÖýø¶È»­±ÊÑÕÉ«£¬ÉèÖý¥±äÉ«ºó£¬¸ÃÏîʧЧ
     public int getProColorInt( ) {
         return proColorInt;
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
         mWidth = getMeasuredWidth();
         mHeight = getMeasuredHeight();

         Paint.FontMetricsInt fontMetrics = paint.getFontMetricsInt();
         baseline =  (mHeight - fontMetrics.bottom + fontMetrics.top) / 2 - fontMetrics.top;


     }

     @Override
     protected void onDraw(Canvas canvas) {
         if (null == mText || "".equals(mText)) return;


         bgPaint.setColor(bgColorInt);
         canvas.drawText(mText, 0, baseline, bgPaint); //»­±³¾°


         float section = (float) curValue / maxValue;
         Rect proRect = new Rect(0, 0, (int) (section * mWidth), mHeight);
         if(!hasGradient){
             paint.setColor(proColorInt);
         }else{
             lg=new LinearGradient(0,0,(int) (section * mWidth),mHeight,color,position, mode);
             paint.setShader(lg);
         }

         canvas.save();
         canvas.clipRect(proRect);
         canvas.drawText(mText, 0, baseline, paint);

         canvas.restore();
     }
 }