如何将结果的 activity 添加到 android-json-form-wizard？
How to add activity for result to android-json-form-wizard?
我正在使用 Android-Json-Form-Wizard library 构建表单生成器；但是，特定项目需要 startactivityforresult 以 return 返回结果作为项目的答案。
因此，我在某些方面更改了库；因此，当我以前回到 activity 时，我遇到了 NullPointerException。
下面是使用的代码。使用 Intent.ACTION_PICK 的部分工作正常，另一个是问题所在。
String key = (String) v.getTag(R.id.key);
String type = (String) v.getTag(R.id.type);
if (JsonFormConstants.CHOOSE_IMAGE.equals(type)) {
getView().hideKeyBoard();
Intent galleryIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
mCurrentKey = key;
getView().startActivityForResult(galleryIntent, RESULT_LOAD_IMG);
} else if(JsonFormConstants.DATE_TIME.equals(type)) {
getView().hideKeyBoard();
Intent dateTimeIntent = new Intent(getView().getContext(), DateTimeActivity.class);
mCurrentKey = key;
getView().startActivityForResult(dateTimeIntent, SELECT_DATE_TIME);
}
错误代码：
03-17 02:08:41.099 30597-30597/br.com.checkd E/AndroidRuntime: FATAL EXCEPTION: main
Process: br.com.checkd, PID: 30597
java.lang.RuntimeException: Unable to start activity ComponentInfo{br.com.checkd/com.vijay.jsonwizard.activities.JsonFormActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
at com.vijay.jsonwizard.mvp.BaseFragment.onCreate(BaseFragment.java:26)
at com.vijay.jsonwizard.fragments.JsonFormFragment.onCreate(JsonFormFragment.java:65)
at android.support.v4.app.Fragment.performCreate(Fragment.java:2068)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1055)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1290)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1272)
at android.support.v4.app.FragmentManagerImpl.dispatchCreate(FragmentManager.java:2144)
at android.support.v4.app.FragmentController.dispatchCreate(FragmentController.java:190)
at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:351)
at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:85)
at com.vijay.jsonwizard.activities.JsonFormActivity.onCreate(JsonFormActivity.java:35)
at android.app.Activity.performCreate(Activity.java:6259)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
基础片段
public abstract class BaseFragment<VS extends ViewState> extends Fragment {
// @Icicle
VS mViewState;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Icepick.restoreInstanceState(this, savedInstanceState);
if (savedInstanceState == null) {
mViewState = createViewState();
mViewState.setSavedInstance(false);
} else {
mViewState.setSavedInstance(true);
}
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// Icepick.saveInstanceState(this, outState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
int layoutRes = getLayoutRes();
if (layoutRes == 0) {
throw new IllegalArgumentException("getLayoutRes() returned 0, which is not allowed. "
+ "If you don't want to use getLayoutRes() but implement your own view for this "
+ "fragment manually, then you have to override onCreateView();");
} else {
View v = inflater.inflate(layoutRes, container, false);
return v;
}
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
@Override
public void onDestroyView() {
super.onDestroyView();
}
/**
* Return the layout resource like R.layout.my_layout
*
* @return the layout resource or null, if you don't want to have an UI
*/
protected int getLayoutRes() {
return 0;
}
protected abstract VS createViewState();
public VS getViewState() {
return mViewState;
}
}
有人可以用它工作吗？
谢谢
尝试始终在使用变量之前对其进行初始化。
public abstract class BaseFragment<VS extends ViewState> extends Fragment {
// @Icicle
VS mViewState;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Icepick.restoreInstanceState(this, savedInstanceState);
if (mViewState == null) mViewState = createViewState();
mViewState.setSavedInstance(savedInstanceState != null);
}
顺便说一句，
@return the layout resource or null,
你不能 return null; 作为 int。尝试使方法成为 Integer return 类型，如果你想要 null 支持
我正在使用 Android-Json-Form-Wizard library 构建表单生成器；但是，特定项目需要 startactivityforresult 以 return 返回结果作为项目的答案。
因此，我在某些方面更改了库；因此，当我以前回到 activity 时，我遇到了 NullPointerException。
下面是使用的代码。使用 Intent.ACTION_PICK 的部分工作正常，另一个是问题所在。
String key = (String) v.getTag(R.id.key);
String type = (String) v.getTag(R.id.type);
if (JsonFormConstants.CHOOSE_IMAGE.equals(type)) {
getView().hideKeyBoard();
Intent galleryIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
mCurrentKey = key;
getView().startActivityForResult(galleryIntent, RESULT_LOAD_IMG);
} else if(JsonFormConstants.DATE_TIME.equals(type)) {
getView().hideKeyBoard();
Intent dateTimeIntent = new Intent(getView().getContext(), DateTimeActivity.class);
mCurrentKey = key;
getView().startActivityForResult(dateTimeIntent, SELECT_DATE_TIME);
}
错误代码：
03-17 02:08:41.099 30597-30597/br.com.checkd E/AndroidRuntime: FATAL EXCEPTION: main
Process: br.com.checkd, PID: 30597
java.lang.RuntimeException: Unable to start activity ComponentInfo{br.com.checkd/com.vijay.jsonwizard.activities.JsonFormActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
at com.vijay.jsonwizard.mvp.BaseFragment.onCreate(BaseFragment.java:26)
at com.vijay.jsonwizard.fragments.JsonFormFragment.onCreate(JsonFormFragment.java:65)
at android.support.v4.app.Fragment.performCreate(Fragment.java:2068)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1055)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1290)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1272)
at android.support.v4.app.FragmentManagerImpl.dispatchCreate(FragmentManager.java:2144)
at android.support.v4.app.FragmentController.dispatchCreate(FragmentController.java:190)
at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:351)
at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:85)
at com.vijay.jsonwizard.activities.JsonFormActivity.onCreate(JsonFormActivity.java:35)
at android.app.Activity.performCreate(Activity.java:6259)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1130)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.vijay.jsonwizard.mvp.ViewState.setSavedInstance(boolean)' on a null object reference
基础片段
public abstract class BaseFragment<VS extends ViewState> extends Fragment {
// @Icicle
VS mViewState;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Icepick.restoreInstanceState(this, savedInstanceState);
if (savedInstanceState == null) {
mViewState = createViewState();
mViewState.setSavedInstance(false);
} else {
mViewState.setSavedInstance(true);
}
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// Icepick.saveInstanceState(this, outState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
int layoutRes = getLayoutRes();
if (layoutRes == 0) {
throw new IllegalArgumentException("getLayoutRes() returned 0, which is not allowed. "
+ "If you don't want to use getLayoutRes() but implement your own view for this "
+ "fragment manually, then you have to override onCreateView();");
} else {
View v = inflater.inflate(layoutRes, container, false);
return v;
}
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
@Override
public void onDestroyView() {
super.onDestroyView();
}
/**
* Return the layout resource like R.layout.my_layout
*
* @return the layout resource or null, if you don't want to have an UI
*/
protected int getLayoutRes() {
return 0;
}
protected abstract VS createViewState();
public VS getViewState() {
return mViewState;
}
}
有人可以用它工作吗？
谢谢
尝试始终在使用变量之前对其进行初始化。
public abstract class BaseFragment<VS extends ViewState> extends Fragment {
// @Icicle
VS mViewState;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Icepick.restoreInstanceState(this, savedInstanceState);
if (mViewState == null) mViewState = createViewState();
mViewState.setSavedInstance(savedInstanceState != null);
}
顺便说一句，
@return the layout resource or null,
你不能 return null; 作为 int。尝试使方法成为 Integer return 类型，如果你想要 null 支持