Android-自定义控件-闪动文字 TextView

效果：

先自定义 MyTextView：

代码语言：javascript复制

public class MyTextView extends android.support.v7.widget.AppCompatTextView {

    private Paint mPaint = null;
    private int mViewWidth = 0;
    private LinearGradient mLinearGradient;
    private Matrix mGradientMatrix;
    private int mTranslate;

    public MyTextView(Context context) {
        super(context);
    }

    public MyTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        if (mViewWidth == 0) {
            mViewWidth = getMeasuredWidth();
            if( mViewWidth > 0 ){
                mPaint = getPaint();
                mLinearGradient = new LinearGradient(0, 0, mViewWidth, 0, new int[]{
                        Color.BLUE,
                        0xffffffff,
                        Color.BLUE
                }, null, Shader.TileMode.CLAMP);
                mPaint.setShader(mLinearGradient);
                mGradientMatrix = new Matrix();
            }
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (mGradientMatrix != null){
            mTranslate  = mViewWidth/5;
            if (mTranslate > 2*mViewWidth){
                mTranslate = -mViewWidth;
            }
            mGradientMatrix.setTranslate(mTranslate, 0);
            mLinearGradient.setLocalMatrix(mGradientMatrix);
            postInvalidateDelayed(100);
        }
    }

}

在布局文件中添加：

代码语言：javascript复制

布局

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