我正在尝试在 HorizontalScrollView 父级内实现自定义视图。自定义视图根据来自 Handler 的时间重复绘制一条线到其 Canvas。现在自定义视图填充了屏幕的宽度（由 548dp 高度限制），我希望线条能够延伸到可见的范围之外。此外，我想让用户能够水平滚动以查看更多行。我尝试将 HorizontalScrollView 的宽度设置为 1500dp（比屏幕宽度大得多），然后尝试水平滚动，但它没有移动。如果视图随着线条越过屏幕的可见部分而滚动，这也是理想的。
我正在开发带有蜂窝的华硕变压器。
这是我正在使用的布局的相关部分：
<HorizontalScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="1500dp"
android:layout_height="548dp"
android:fillViewport="true" >
<maavapp.layout.CustomDraw
android:id="@+id/custom_draw"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
</maavapp.layout.CustomDraw>
</HorizontalScrollView>
这是 CustomDraw 类的代码：
public class CustomDraw extends View {
private static int mSelected;
private ArrayList<Coordinate> measure1;
private ArrayList<Coordinate> measure2;
private ArrayList<Coordinate> measure3;
private boolean north = false, east = true, south = true, west = false;
private DrawHandler dh = new DrawHandler();
private boolean draw = true;
private int width;
private int height;
private int m2;
public CustomDraw(Context context) {
super(context);
init();
}
public CustomDraw(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public CustomDraw(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public void init() {
measure1 = new ArrayList<Coordinate>();
measure2 = new ArrayList<Coordinate>();
measure3 = new ArrayList<Coordinate>();
mSelected = Constants.MEASURE_1;
width = 0;
height = 0;
m2 = 0;
}
public void setMeasure(int measure) {
mSelected = measure;
}
public void toggleDraw() {
draw = !draw;
if(draw) {
updateLine();
}
}
public boolean isDrawing() {
return draw;
}
public void updateLine() {
// grab new coordinates for each measure
/*new_coord(measure1);
new_coord(measure2);
new_coord(measure3);*/
if(measure1.isEmpty() && measure2.isEmpty() && measure3.isEmpty()) {
measure1.add(new Coordinate(0, 0));
measure2.add(new Coordinate(0, 0));
measure3.add(new Coordinate(0, 0));
} else {
Coordinate last_coord = measure1.get(measure1.size() - 1);
measure2.add(new Coordinate(++m2, 25));
/*if(last_coord.x >= width) {
east = false;
west = true;
} else if(last_coord.x <= 0) {
east = true;
west = false;
}*/
if(last_coord.y >= height) {
south = false;
north = true;
} else if(last_coord.y <= 0) {
south = true;
north = false;
}
Log.d("MAAV", "last_coord.x + 3: " + (last_coord.x + 3));
Log.d("MAAV", "last_coord.y + 3: " + (last_coord.y + 3));
if(south && east) {
measure1.add(new Coordinate(last_coord.x + 3, last_coord.y + 3));
} else if(south && west) {
measure1.add(new Coordinate(last_coord.x - 3, last_coord.y + 3));
} else if(north && east) {
measure1.add(new Coordinate(last_coord.x + 3, last_coord.y - 3));
} else if(north && west) {
measure1.add(new Coordinate(last_coord.x - 3, last_coord.y - 3));
}
}
if(draw) {
dh.sleep(10);
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
this.width = w;
this.height = h;
super.onSizeChanged(w, h, oldw, oldh);
}
@Override
public void onDraw(Canvas c) {
super.onDraw(c);
Paint p = new Paint();
p.setStyle(Paint.Style.FILL);
p.setColor(Color.WHITE);
c.drawPaint(p);
p.setColor(Color.BLACK);
switch(mSelected) {
case Constants.MEASURE_1:
for(int i = 0; i < measure1.size(); i++) {
Coordinate coord = measure1.get(i);
Log.d("MAAV", "drawing coord.x, coord.y: " + (coord.x) + ", " + (coord.y));
c.drawRect(coord.x, coord.y, coord.x + 3, coord.y + 3, p);
}
break;
case Constants.MEASURE_2:
for(int i = 0; i < measure2.size(); i++) {
Coordinate coord = measure2.get(i);
c.drawRect(coord.x, coord.y, coord.x + 3, coord.y + 3, p);
}
break;
case Constants.MEASURE_3:
for(int i = 0; i < measure2.size(); i++) {
Coordinate coord = measure2.get(i);
c.drawRect(coord.x, coord.y, coord.x + 3, coord.y + 3, p);
}
break;
}
}
class DrawHandler extends Handler {
@Override
public void handleMessage(Message msg) {
CustomDraw.this.updateLine();
CustomDraw.this.invalidate();
}
public void sleep(long delayMillis) {
this.removeMessages(0);
sendMessageDelayed(obtainMessage(0), delayMillis);
}
}
}
谢谢你的帮助！