Android单行文本跑马灯控件
public class AutoScrollTextView extends TextView implements OnClickListener {
public final static String TAG = AutoScrollTextView.class.getSimpleName();
private int runNum = 1;// 滚动次数
private float textLength = 0f;// 文本长度
private float viewWidth = 0f;
private float step = 0f;// 文字的横坐标
private float y = 0f;// 文字的纵坐标
private float temp_view_plus_text_length = 0.0f;// 用于计算的临时变量
private float temp_view_plus_two_text_length = 0.0f;// 用于计算的临时变量
public boolean isStarting = false;// 是否开始滚动
private Paint paint = null;// 绘图样式
private Paint paint1 = null;// 绘图样式
private String text = “”;// 文本内容
private boolean isFade = true;// 是否加影子
private float layout_width = 168f;
public float getLayout_width() {
return layout_width;
}
public void setLayout_width(float layoutWidth) {
layout_width = layoutWidth;
}
public boolean isFade() {
return isFade;
}
public void setFade(boolean isFade) {
this.isFade = isFade;
}
public AutoScrollTextView(Context context) {
super(context);
initView();
}
public AutoScrollTextView(Context context, AttributeSet attrs) {
super(context, attrs);
initView();
}
public AutoScrollTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView();
}
/** */
/**
* 初始化控件
*/
private void initView() {
setOnClickListener(this);
}
/** */
/**
* 文本初始化,每次更改文本内容或者文本效果等之后都需要重新初始化一下
*/
public void init(WindowManager windowManager) {
paint = getPaint();
paint1 = new Paint();
paint1.setColor(Color.WHITE);
paint1.setTextSize(getTextSize());
text = getText().toString();
textLength = paint.measureText(text);
viewWidth = layout_width * LogoActivity.screenHeight / 960;
if (textLength > viewWidth * 2) {
isStarting = true;
}
Log.e(" textLength ", textLength + " " + viewWidth);
if (viewWidth == 0) {
if (windowManager != null) {
Display display = windowManager.getDefaultDisplay();
viewWidth = display.getWidth();
}
}
temp_view_plus_text_length = viewWidth + textLength;
temp_view_plus_two_text_length = viewWidth + textLength * 2;
step = temp_view_plus_text_length;
y = getTextSize() + getPaddingTop();
}
@Override
public Parcelable onSaveInstanceState() {
Parcelable superState = super.onSaveInstanceState();
SavedState ss = new SavedState(superState);
ss.step = step;
ss.isStarting = isStarting;
return ss;
}
@Override
public void onRestoreInstanceState(Parcelable state) {
if (!(state instanceof SavedState)) {
super.onRestoreInstanceState(state);
return;
}
SavedState ss = (SavedState) state;
super.onRestoreInstanceState(ss.getSuperState());
step = ss.step;
isStarting = ss.isStarting;
}
public static class SavedState extends BaseSavedState {
public boolean isStarting = false;
public float step = 0.0f;
SavedState(Parcelable superState) {
super(superState);
}
@Override
public void writeToParcel(Parcel out, int flags) {
super.writeToParcel(out, flags);
out.writeBooleanArray(new boolean[] { isStarting });
out.writeFloat(step);
}
public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() {
public SavedState[] newArray(int size) {
return new SavedState[size];
}
@Override
public SavedState createFromParcel(Parcel in) {
return new SavedState(in);
}
};
private SavedState(Parcel in) {
super(in);
boolean[] b = null;
in.readBooleanArray(b);
if (b != null && b.length > 0)
isStarting = b[0];
step = in.readFloat();
}
}
/** */
/**
* 开始滚动
*/
public void startScroll() {
isStarting = true;
invalidate();
}
/** */
/**
* 停止滚动
*/
public void stopScroll() {
isStarting = false;
runNum = 1;
invalidate();
}
@Override
public void onDraw(Canvas canvas) {
if (isFade)canvas.drawText(text, temp_view_plus_text_length - step, y, paint1);
canvas.drawText(text, temp_view_plus_text_length - step, y - 1, paint);
if (!isStarting) {
return;
}
step += 1;
if (step > temp_view_plus_two_text_length) {
step = textLength - viewWidth;
runNum--;
}
if (runNum == 0 && step == temp_view_plus_text_length) {
isStarting = false;
}
invalidate();
}
@Override
public void onClick(View v) {
// if (isStarting)
// stopScroll();
// else
// startScroll();
}
}