android中如何正确的设置view的多个tag值

    在android开发过程中,我们经常会用到view.setTag(object)这个方法,特别是在ListView的自定义的adapter中复用view的时候。同时,view还提供了设置多个tag数据的方法,即view.setTag(int,Object),其中这个int值需要设置正确,不然这个方法会报错了。让我们来看看怎么设置这个值。先看结果:
android中如何正确的设置view的多个tag值_第1张图片
    从eclipse打印的log可以看出,我设置了gridview的4种不同类型的tag值。再来看看代码。

package com.androidtest.scroll;

import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.Button;
import android.widget.GridView;
import android.widget.TextView;

import com.androidtest.R;
import com.androidtest.base.BaseActivity;

public class GridViewActivity extends BaseActivity implements OnClickListener{

    private TextView title;
    private GridView gridView;
    private Button btn_setTag,btn_getTag;

    private final static int five=5<<24;
    private final static int six=6<<24;
    private final static int serven=7<<24;
    private final static int eight=8<<24;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_gridview);

        init();

    }

    private void init() {
        title=(TextView) findViewById(R.id.title);
        title.setText("test gridview");

        findViewById(R.id.back).setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                finish();
            }
        });

        rootView=findViewById(R.id.rootView);

        btn_getTag=(Button) findViewById(R.id.btn_getTag);
        btn_setTag=(Button) findViewById(R.id.btn_setTag);
        btn_setTag.setOnClickListener(this);
        btn_getTag.setOnClickListener(this);

        gridView=(GridView) findViewById(R.id.gridView);
        gridView.setAdapter(createAdapter());
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        if(v==btn_getTag) {
            getTag();
        }else if(v==btn_setTag) {
            setTag();
        }
    }

    private void setTag() {
        gridView.setTag(five,"hello world");
        gridView.setTag(six,true);
        gridView.setTag(serven,100);
        gridView.setTag(eight,158.9f);
    }

    private void getTag() {
        Log.e("gridview getTag(index)", 
        "String:"+((String)gridView.getTag(five)));
        Log.e("gridview getTag(index)", "boolean:"+
        ((Boolean)gridView.getTag(six)));
        Log.e("gridview getTag(index)", "int:"+
        ((Integer)gridView.getTag(serven)));
        Log.e("gridview getTag(index)", "float:"+
        ((Float)gridView.getTag(eight)));
    }
}

运行界面:
android中如何正确的设置view的多个tag值_第2张图片

    view.setTag(int,Object)中的int值必须要左移24位才行,这样才不会报错。

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