我有一个自定义视图,我显示两个矩形。我想通过从mainactivity发送的变量来设置高度。
我的customview类如下。
package com.example.customview;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;
public class MyView extends View {
Paint paint;
Paint paint2;
public MyView(Context context, AttributeSet attrs) {
super(context, attrs);
paint = new Paint();
paint2 = new Paint();
}
@Override
protected void onDraw(Canvas canvas) {
paint.setColor(Color.RED);
paint2.setColor(Color.DKGRAY);
canvas.drawRect(150, 0, 200, 100, paint);
canvas.drawRect(200, 0, 250, 150, paint2);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(400, 300);
}
}
主要类是标准的
package com.example.customview;
import android.app.Activity;
import android.os.Bundle;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
如何更改oncreate或onstart的高度。
感谢大家的帮助。
答案 0 :(得分:0)
您需要从主要活动发送数据并从MyView接收数据。当您创建从主要用途
打开新活动的意图时_YourIntent_.putExtra(_tag_,_yourData_);
startActivityForResult(_YourIntent_, result);
//put extra is simply for sending data, and to receive it the other hand , oncreate use this;
Intent x = getIntent();``
//now get the data
int _yourvariable_ = x.getExtras().getString(_tag_).toint;
答案 1 :(得分:0)
您需要创建一个变量并从Activity中设置它。例如:
private int mHeight = 0;
@Override
protected void onDraw(Canvas canvas) {
paint.setColor(Color.RED);
paint2.setColor(Color.DKGRAY);
canvas.drawRect(150, 0, 200, 150 + mHeight, paint);
canvas.drawRect(200, 0, 250, 200 + mHeight, paint2);
}
public void setRectHeight(final int height) {
mHeight = height;
invalidate();
}
并设置活动的高度:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MyView view = (MyView)findViewById(R.id.my_view);
view.setHeight(50);
}