我在我的应用程序中有一个类来显示一些按钮，当用户点击按钮时，它会跳转到webview活动以查看某个网页，因此我在about类中定义了url，然后设置onlick方法将它们传递给用于打开网页的相同webview活动，但是在运行此活动时我不断得到一个好奇的NullPointerException，而我的logcat只打印
12-02 09：03：11.815：WARN / ActivityManager（51）：活动空闲超时 for HistoryRecord {44d68ea0 com.appkon.hdtvs / .About} 12-02 09：03：17.026：WARN / ActivityManager（51）：活动销毁超时 HistoryRecord {44e37518 com.appkon.hdtvs / .HDtvs}
这是我的代码。非常感谢，谢谢
About.java
public class About extends Activity{
private Button backbutton;
private Button likebutton;
private ImageView versionlogo;
private ImageButton faq;
private ImageButton forum;
private ImageButton feedback;
private ImageButton rate;
private String likepath ="http://appkon.com/hdtvs/share.html";
private String likename = "分享";
private String lpath="" ;
private String lname="" ;
private String faqpath ="http://appkon.com/hdtvs/faq.html";
private String faqname ="常见问题";
private String forumpath= "http://appkon.com/forum/" ;
private String forumname = "APP论坛";
private String fqpath="";
private String fqname="";
private String frpath="";
private String frname="";
private String ratepath ="http://appkon.com/hdtvs/";
private String ratename="评价";
private String rpath="";
private String rname="";
private String feedbackpath ="http://appkon.com/hdtvs/feedback.html";
private String feedbackname="反馈问题";
private String fdname="";
private String fdpath="";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
backbutton=(Button) findViewById(R.id.back);
likebutton=(Button) findViewById(R.id.share);
faq =(ImageButton)findViewById(R.id.faqbutton);
forum =(ImageButton)findViewById(R.id.forumbutton);
feedback =(ImageButton)findViewById(R.id.feedbackbutton);
rate =(ImageButton)findViewById(R.id.ratebutton);
backbutton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, HDtvs.class);
startActivity(intent);
About.this.finish();
}
});
likebutton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, Renrenframe.class);
startActivity(intent);
About.this.finish();
}
});
faq.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, Aboutframe.class);
Bundle bundle = new Bundle();
bundle.putString("fqpath",faqpath);
bundle.putString("fqname",faqname);
intent.putExtras(bundle);
startActivity(intent);
About.this.finish();
}
});
feedback.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, Aboutframe.class);
Bundle bundle = new Bundle();
bundle.putString("fdpath",feedbackpath);
bundle.putString("fdname",feedbackname);
intent.putExtras(bundle);
startActivity(intent);
About.this.finish();
}
});
rate.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, Aboutframe.class);
Bundle bundle = new Bundle();
bundle.putString("rpath",ratepath);
bundle.putString("rname",ratename);
intent.putExtras(bundle);
startActivity(intent);
About.this.finish();
}
});
forum.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(About.this, Aboutframe.class);
Bundle bundle = new Bundle();
bundle.putString("frpath",forumpath);
bundle.putString("frname",forumname);
intent.putExtras(bundle);
startActivity(intent);
About.this.finish();
}
});
}
}
Aboutframe.java
public class Aboutframe extends Activity{
private TextView namebar;
private ImageButton likebutton;
private ImageButton backbutton;
private WebView aboutframe;
private String lpath ;
private String lname ;
private String fqpath;
private String fqname;
private String frpath;
private String frname;
private String rpath;
private String rname;
private String fdname;
private String fdpath;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.aboutframe);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);//remove title bar
backbutton=(ImageButton) findViewById(R.id.back);
likebutton=(ImageButton) findViewById(R.id.share);
aboutframe =(WebView)findViewById(R.id.aboutframe);
Intent intent=this.getIntent();
Bundle bunde = intent.getExtras();
lname = bunde.getString("lname");
lpath = bunde.getString("lpath");
fqname = bunde.getString("fqname");
fqpath = bunde.getString("fqpath");
frname = bunde.getString("frname");
frpath = bunde.getString("frpath");
rname = bunde.getString("rname");
rpath = bunde.getString("rpath");
fdname = bunde.getString("fdname");
fdpath = bunde.getString("fdpath");
if(lname != null&lpath!= null){
namebar.setText(lname);
aboutframe.setWebViewClient(new WebViewClient(){
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(lpath);
return true;
}
});
}
if(fqname != null&fqpath!= null){
namebar.setText(fqname);
aboutframe.setWebViewClient(new WebViewClient(){
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(fqpath);
return true;
}
});
}
if(frname != null&frpath!= null){
namebar.setText(frname);
aboutframe.setWebViewClient(new WebViewClient(){
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(frpath);
return true;
}
});
}
if(rname != null&rpath!= null){
namebar.setText(rname);
aboutframe.setWebViewClient(new WebViewClient(){
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(rpath);
return true;
}
});
}
if(fdname != null&fdpath!= null){
namebar.setText(fdname);
aboutframe.setWebViewClient(new WebViewClient(){
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(fdpath);
return true;
}
});
backbutton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(Aboutframe.this, About.class);
startActivity(intent);
Aboutframe.this.finish();
}
});
likebutton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent();
intent.setClass(Aboutframe.this, Renrenframe.class);
startActivity(intent);
Aboutframe.this.finish();
}
});
}
}
}
答案 0 :(得分：0)
该错误意味着您的活动超时。
我不明白你打电话的原因：
aboutframe.setWebViewClient
多次。您可以尝试将if's替换为if else's：
/*...*/
else if(frname != null&frpath!= null){
/*...*/
else if(rname != null&rpath!= null){
/*...*/
答案 1 :(得分：0)
将所有代码放在
之间try
{
your Code here...
}
catch(NullPointerException e)
{
e.printStackTrace();
}
答案 2 :(得分：0)
您最好使用&&代替&。后者是“二进制”，你想使用“逻辑和”。