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import android.content.Context;
import android.graphics.Canvas;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.widget.TextView;
public class MarqueeText extends TextView {
/** 是否停止滚动 */
private boolean mStopMarquee;
private String mText;
private float mCoordinateX;
private float mTextWidth;
public MarqueeText(Context context, AttributeSet attrs) {
super(context, attrs);
}
public void setText(String text) {
this.mText = text;
mTextWidth = getPaint().measureText(mText);
if (mHandler.hasMessages(0))
mHandler.removeMessages(0);
if (mText.length() > 15) {
mHandler.sendEmptyMessageDelayed(0, 2000);
}else {
invalidate();
}
}
@Override
protected void onAttachedToWindow() {
mStopMarquee = false;
if(mText == null || mText.length() <= 0){
return;
}
if (mText.length() > 15) {
mHandler.sendEmptyMessageDelayed(0, 800);
}
super.onAttachedToWindow();
}
@Override
protected void onDetachedFromWindow() {
mStopMarquee = true;
if (mHandler.hasMessages(0))
mHandler.removeMessages(0);
super.onDetachedFromWindow();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if(mText == null || mText.length() <= 0){
return;
}
// if (mText.length() > 15) {
canvas.drawText(mText, mCoordinateX, 40, getPaint());
// }
}
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 0:
if (Math.abs(mCoordinateX) > (mTextWidth + 100)) {
mCoordinateX = 0;
invalidate();
if (!mStopMarquee) {
sendEmptyMessageDelayed(0, 500);
}
} else {
mCoordinateX -= 1;
invalidate();
if (!mStopMarquee) {
sendEmptyMessageDelayed(0, 30);
}
}
break;
}
super.handleMessage(msg);
}
};
}