Android无法突出显示listview中的项目

我试图突出显示listview中的一个项目，所以当用户单击listview中的一个项目时，会启动一个新活动，并且listview中的特定项目会突出显示

我知道这可以用片段完成，但我更喜欢活动，因为它使我的工作更容易

这里是自定义适配器

public class CustomAdapter extends BaseAdapter{

    Context mycontext;
    ArrayList<String> contactsList;
    LayoutInflater minflater;

    public CustomAdapter(Context context, ArrayList<String> list)
    {
        this.mycontext=context;
        contactsList=list;
        minflater =LayoutInflater.from(context);

    }
    @Override
    public int getCount()
    {
        return contactsList.size();
    }


    @Override
    public Object getItem(int position)
    {
        return contactsList.get(position);
    }


    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }


    @Override
    public View getView(int position,View convertView,ViewGroup parent)
    {
        View v=convertView;

        if (convertView !=null)
        {
            LayoutInflater inflater=(LayoutInflater) mycontext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v =inflater.inflate(R.layout.item_layout,null);

            TextView tv=(TextView)v.findViewById(R.id.itemName);

            if (position ==1)
            {
                convertView.setBackgroundColor(Color.BLUE);

            }
        }
        return  convertView;
    }
}

如果listview位置索引为1，我尝试将项目膨胀并以蓝色突出显示textview。我做错了什么

编辑2：

 1810-1810/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.example.listviewandroid, PID: 1810
    java.lang.NullPointerException
            at android.widget.AbsListView.obtainView(AbsListView.java:2265)
            at android.widget.ListView.measureHeightOfChildren(ListView.java:1263)
            at android.widget.ListView.onMeasure(ListView.java:1175)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
            at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1052)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:590)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1916)
            at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1113)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1295)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5670)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
            at android.view.Choreographer.doCallbacks(Choreographer.java:574)
            at android.view.Choreographer.doFrame(Choreographer.java:544)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)

编辑3：主要活动代码

package com.example.listviewandroid;

import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import android.text.format.Time;
import java.util.Date;

public class MainActivity extends Activity {
    ListView listView ;
    static final  String STE = "";
    static final String STM = "";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (savedInstanceState !=null)
        {
            restoreState(savedInstanceState);
        }
        listView = (ListView) findViewById(R.id.listView);

        TextView textviewmenu= (TextView) findViewById(R.id.textViewMenu);
        textviewmenu.setBackgroundColor(Color.rgb(89,89,89));
        textviewmenu.setTextColor(Color.WHITE);

        String[] values = getResources().getStringArray(R.array.menuList);

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, android.R.id.text1, values);


        // Assign adapter to ListView
        listView.setAdapter(adapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {

                // ListView Clicked item index
                int itemPosition     = position;

                // ListView Clicked item value
                String  itemValue    = (String) listView.getItemAtPosition(position);


                // Show Alert

                switch( position )
                {

                    case 1:  Intent newActivity = new Intent(MainActivity.this,Activity2.class);
                        startActivity(newActivity);
                        break;

                    case 2:  Intent newActivity1 = new Intent(MainActivity.this,Activity3.class);
                        startActivity(newActivity1);
                        break;
                    case 3:  Intent newActivity2 = new Intent(MainActivity.this,Activity4.class);
                        startActivity(newActivity2);
                        break;
                    case 4:  Intent newActivity3 = new Intent(MainActivity.this,Activity5.class);
                        startActivity(newActivity3);
                        break;
                    case 5:  Intent newActivity4 = new Intent(MainActivity.this,Activity6.class);
                        startActivity(newActivity4);
                        break;

                }
                Toast.makeText(getApplicationContext(),
                        "Position :"+itemPosition+"  ListItem : " +itemValue , Toast.LENGTH_LONG)
                        .show();

            }

        });
        Time now = new Time();
        now.setToNow();
        if (savedInstanceState ==null )
        {
        TextView textview2= (TextView)findViewById(R.id.MAtextView2);
        textview2.setText(now.hour+" : "+now.minute);
        }


    }


    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);


        TextView startimetext= (TextView) findViewById(R.id.MAtextView2);
        outState.putString(STE,startimetext.getText().toString());



        TextView endtimetext= (TextView) findViewById(R.id.MAtextView3);
        outState.putString(STM,startimetext.getText().toString());


    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    public void SetEndTime(View view) {
        Time now = new Time();
        now.setToNow();
        TextView textview3= (TextView)findViewById(R.id.MAtextView3);
        textview3.setText(now.hour+" : "+now.minute);

    }

    public void NextActivity(View view) {
        Intent myIntent = new Intent(MainActivity.this,Activity2.class);
       MainActivity.this.startActivity(myIntent);
        this.overridePendingTransition(android.R.anim.slide_in_left,android.R.anim.slide_out_right);

    }

    private void restoreState(Bundle savedInstanceState) {
        TextView startimetext= (TextView) findViewById(R.id.MAtextView2);

        TextView endtimetext= (TextView) findViewById(R.id.MAtextView3);


      startimetext.setText(savedInstanceState.getString(STE));
      endtimetext.setText(savedInstanceState.getString(STM));



    }
}

package com.example.listviewandroid；
导入android.content.Intent；
导入android.graphics.Color；
导入android.os.Bundle；
导入android.app.Activity；
导入android.view.Menu；
导入android.view.view；
导入android.widget.AdapterView；
导入android.widget.ArrayAdapter；
导入android.widget.EditText；
导入android.widget.ListView；
导入android.widget.Spinner；
导入android.widget.TextView；
导入android.widget.Toast；
导入android.text.format.Time；
导入java.util.Date；
公共类MainActivity扩展了活动{
列表视图列表视图；
静态最终字符串STE=“”；
静态最终字符串STM=“”；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity_main）；
如果（savedInstanceState！=null）
{
恢复性房地产（savedInstanceState）；
}
listView=（listView）findViewById（R.id.listView）；
TextView textviewmenu=（TextView）findViewById（R.id.textviewmenu）；
textviewmenu.setBackgroundColor（Color.rgb（89,89,89））；
textviewmenu.setTextColor（Color.WHITE）；
String[]values=getResources（）.getStringArray（R.array.menuList）；
ArrayAdapter=新的ArrayAdapter（此，
android.R.layout.simple_list_item_1，android.R.id.text1，值）；
//将适配器分配给ListView
setAdapter（适配器）；
setOnItemClickListener（新的AdapterView.OnItemClickListener（）{
@凌驾
public void onItemClick（AdapterView父级、视图、，
内部位置，长id）{
//ListView单击的项目索引
int itemPosition=位置；
//ListView单击的项目值
String itemValue=（String）listView.getItemAtPosition（position）；
//显示警惕
开关（位置）
{
案例1:Intent newActivity=newintent（MainActivity.this，Activity2.class）；
星触觉（新活动）；
打破
案例2:Intent newActivity1=新Intent（MainActivity.this，Activity3.class）；
startActivity（新活动1）；
打破
案例3:Intent newActivity2=新Intent（MainActivity.this，Activity4.class）；
startActivity（新活动2）；
打破
案例4:Intent newActivity3=新的Intent（MainActivity.this，Activity5.class）；
startActivity（新活动3）；
打破
案例5:Intent newActivity4=新的Intent（MainActivity.this，Activity6.class）；
startActivity（新活动4）；
打破
}
Toast.makeText（getApplicationContext（），
位置：“+itemPosition+”列表项：“+itemValue，Toast.LENGTH\u LONG）
.show（）；
}
});
现在时间=新时间（）；
现在，setToNow（）；
如果（savedInstanceState==null）
{
TextView textview2=（TextView）findViewById（R.id.MAtextView2）；
textview2.setText（now.hour+：“+now.minute）；
}
}
@凌驾
SaveInstanceState上受保护的无效（束超出状态）{
super.onSaveInstanceState（超出状态）；
TextView startimetext=（TextView）findViewById（R.id.MAtextView2）；
putString（STE，startimetext.getText（）.toString（））；
TextView endtimetext=（TextView）findViewById（R.id.MAtextView3）；
putString（STM，startimetext.getText（）.toString（））；
}
@凌驾
公共布尔onCreateOptions菜单（菜单）{
//为菜单充气；这会将项目添加到操作栏（如果存在）。
getMenuInflater（）.充气（R.menu.main，menu）；
返回true；
}
公共void SetEndTime（视图）{
现在时间=新时间（）；
现在，setToNow（）；
TextView textview3=（TextView）findViewById（R.id.MAtextView3）；
textview3.setText（now.hour+：“+now.minute）；
}
公共空间无接触性（视图）{
Intent myIntent=新的Intent（MainActivity.this、Activity2.class）；
MainActivity.this.startActivity（myIntent）；
这个.overridePendingTransition（android.R.anim.slide\u in\u left，android.R.anim.slide\u out\u right）；
}
私有财产（捆绑保存状态）{
TextView startimetext=（TextView）findViewById（R.id.MAtextView2）；
TextView endtimetext=（TextView）findViewById（R.id.MAtextView3）；
startimetext.setText（savedInstanceState.getString（STE））；
setText（savedInstanceState.getString（STM））；
}
}

将

if（convertView！=null）

更改为

if（convertView==null）

当您没有可重用的视图时，需要对布局进行充气

您需要在listview上添加一个单击侦听器，以突出显示特定的行/列表项。下面是如何添加单击侦听器。更新您的视图以突出显示它

lv.setOnItemClickListener（新的OnItemClickListener（）{

@覆盖
public void onItemClick（AdapterView父视图、视图、整型位置、，
长id）{
意向意向=新意向（MainActivity.this，SendMessage
 1810-1810/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.example.listviewandroid, PID: 1810
    java.lang.NullPointerException
            at android.widget.AbsListView.obtainView(AbsListView.java:2265)
            at android.widget.ListView.measureHeightOfChildren(ListView.java:1263)
            at android.widget.ListView.onMeasure(ListView.java:1175)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
            at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1052)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:590)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
            at android.view.View.measure(View.java:16497)
            at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1916)
            at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1113)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1295)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5670)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
            at android.view.Choreographer.doCallbacks(Choreographer.java:574)
            at android.view.Choreographer.doFrame(Choreographer.java:544)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)

package com.example.listviewandroid;

import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import android.text.format.Time;
import java.util.Date;

public class MainActivity extends Activity {
    ListView listView ;
    static final  String STE = "";
    static final String STM = "";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (savedInstanceState !=null)
        {
            restoreState(savedInstanceState);
        }
        listView = (ListView) findViewById(R.id.listView);

        TextView textviewmenu= (TextView) findViewById(R.id.textViewMenu);
        textviewmenu.setBackgroundColor(Color.rgb(89,89,89));
        textviewmenu.setTextColor(Color.WHITE);

        String[] values = getResources().getStringArray(R.array.menuList);

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, android.R.id.text1, values);


        // Assign adapter to ListView
        listView.setAdapter(adapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {

                // ListView Clicked item index
                int itemPosition     = position;

                // ListView Clicked item value
                String  itemValue    = (String) listView.getItemAtPosition(position);


                // Show Alert

                switch( position )
                {

                    case 1:  Intent newActivity = new Intent(MainActivity.this,Activity2.class);
                        startActivity(newActivity);
                        break;

                    case 2:  Intent newActivity1 = new Intent(MainActivity.this,Activity3.class);
                        startActivity(newActivity1);
                        break;
                    case 3:  Intent newActivity2 = new Intent(MainActivity.this,Activity4.class);
                        startActivity(newActivity2);
                        break;
                    case 4:  Intent newActivity3 = new Intent(MainActivity.this,Activity5.class);
                        startActivity(newActivity3);
                        break;
                    case 5:  Intent newActivity4 = new Intent(MainActivity.this,Activity6.class);
                        startActivity(newActivity4);
                        break;

                }
                Toast.makeText(getApplicationContext(),
                        "Position :"+itemPosition+"  ListItem : " +itemValue , Toast.LENGTH_LONG)
                        .show();

            }

        });
        Time now = new Time();
        now.setToNow();
        if (savedInstanceState ==null )
        {
        TextView textview2= (TextView)findViewById(R.id.MAtextView2);
        textview2.setText(now.hour+" : "+now.minute);
        }


    }


    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);


        TextView startimetext= (TextView) findViewById(R.id.MAtextView2);
        outState.putString(STE,startimetext.getText().toString());



        TextView endtimetext= (TextView) findViewById(R.id.MAtextView3);
        outState.putString(STM,startimetext.getText().toString());


    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    public void SetEndTime(View view) {
        Time now = new Time();
        now.setToNow();
        TextView textview3= (TextView)findViewById(R.id.MAtextView3);
        textview3.setText(now.hour+" : "+now.minute);

    }

    public void NextActivity(View view) {
        Intent myIntent = new Intent(MainActivity.this,Activity2.class);
       MainActivity.this.startActivity(myIntent);
        this.overridePendingTransition(android.R.anim.slide_in_left,android.R.anim.slide_out_right);

    }

    private void restoreState(Bundle savedInstanceState) {
        TextView startimetext= (TextView) findViewById(R.id.MAtextView2);

        TextView endtimetext= (TextView) findViewById(R.id.MAtextView3);


      startimetext.setText(savedInstanceState.getString(STE));
      endtimetext.setText(savedInstanceState.getString(STM));



    }
}

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {
        Intent intent = new Intent(MainActivity.this, SendMessage.class);
        String message = "abc";
        intent.putExtra(EXTRA_MESSAGE, message);
        startActivity(intent);
    }
});

@Override
    public View getView(int position, View convertView, ViewGroup parent) {

    if (convertView == null) {

                LayoutInflater inflater = (LayoutInflater) context
                        .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.item_layout, null);
            } 
                TextView tv=(TextView)convertView .findViewById(R.id.itemName);

                 try {

            if(position ==1){

                convertView.setBackgroundColor(Color.GREEN);
            }


        } catch (Exception e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }


return  convertView;

}

private int selectedIndex;
    private int selectedColor = Color.parseColor("#1b1b1b");


In your adapter class; add this method:

public void setSelectedIndex(int position)
    {
        selectedIndex = position;
        notifyDataSetChanged();
    }

if(selectedIndex!= -1 && position == selectedIndex)
        {
            txtTitle.setBackgroundColor(Color.BLACK);
        }
        else
        {
            txtTitle.setBackgroundColor(selectedColor);
        }

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View view,
                int position, long id) {
            AnyObject obj=(AnyObject)arg0.getItemAtPosition(position);

                            ........
                            .........
                            .........

        }
    });