Android apk未安装
我正在安装和测试本地html文件。这不起作用,我不幸被阻止了。然后我尝试了简单的活动,没有任何创建。但我还是遇到了同样的问题。没有应用程序未安装。android:minSdkVersion=“8”android:targetSdkVersion=“16” 代码:Android apk未安装,android,eclipse,nullpointerexception,apk,Android,Eclipse,Nullpointerexception,Apk,我正在安装和测试本地html文件。这不起作用,我不幸被阻止了。然后我尝试了简单的活动,没有任何创建。但我还是遇到了同样的问题。没有应用程序未安装。android:minSdkVersion=“8”android:targetSdkVersion=“16” 代码: 您已经用较高版本安装了相同的应用程序,因此无法安装较低版本的应用程序。尝试此操作 mContext未初始化。请尝试初始化它 mContext = this; 在onCreate内部,您需要在copyFile()中传递mContext参
您已经用较高版本安装了相同的应用程序,因此无法安装较低版本的应用程序。尝试此操作
mContext
未初始化。请尝试初始化它
mContext = this;
在
onCreate
内部,您需要在copyFile()
中传递mContext
参数
选中此项:
在onCreate()
中,执行以下操作:filef=copyFile(R.raw.index,“index.html”,mContext)代码>
也可以使用MainActivity来代替mContext
。这类似于:
File f=copyFile(R.raw.index,“index.html”,MainActivity.this)代码>
希望这能有所帮助。您有一个NullPointerException
@line 55MainActivity.java
请发布您的MainActivity.java代码。错误位于第55行和第35行。请检查清单文件@siddharth:如何检测哪几行之间的错误??就像你说的55岁和55岁35@Siddharth:检查我编辑的代码。@user3602987:检查Hariharan的答案。@user3602987您在哪里添加了那一行?Context mContext=this;
public class MainActivity extends Activity {
Context mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mContext = this;
File f = copyFile(R.raw.index, "index.html");
File file = new File(f.getAbsolutePath());
String extension = android.webkit.MimeTypeMap.getFileExtensionFromUrl(Uri.fromFile(file).toString());
String mimetype = android.webkit.MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
Intent i = new Intent(Intent.ACTION_VIEW);
// i.setClassName("com.google.glass.browser", "com.google.glass.browser.WebBrowserActivity");
i.setClassName("com.google.android.browser", "com.android.browser.BrowserActivity");
i.setDataAndType(Uri.fromFile(file),mimetype);
mContext.startActivity(i);
}
private File copyFile(int resourceId, String filename) {
InputStream in = null;
OutputStream out = null;
File outFile = null;
try {
in = mContext.getResources().openRawResource(resourceId);
outFile = new File(mContext.getExternalFilesDir(null), filename);
Log.d("Test", "output file" + outFile.getAbsolutePath());
out = new FileOutputStream(outFile);
byte[] buffer = new byte[1024];
int read;
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
} catch(IOException e) {
Log.e("Test", "Failed to copy file", e);
} finally {
try {
in.close();
out.flush();
out.close();
in = null;
out = null;
} catch (Exception e){}
}
return outFile;
}
mContext = this;
private File copyFile(int resourceId, String filename, Context mContext) {
InputStream in = null;
OutputStream out = null;
File outFile = null;
try {
in = mContext.getResources().openRawResource(resourceId);
outFile = new File(mContext.getExternalFilesDir(null), filename);
Log.d("Test", "output file" + outFile.getAbsolutePath());
out = new FileOutputStream(outFile);
byte[] buffer = new byte[1024];
int read;
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
} catch(IOException e) {
Log.e("Test", "Failed to copy file", e);
} finally {
try {
in.close();
out.flush();
out.close();
in = null;
out = null;
} catch (Exception e){}
}
return outFile;
}