如何在Android中开始活动?(How to start an activity in Android?)
我是android编程的新手。 我想使用一个代码,通过单击Button,从我当前的活动中将我带到MainActivity。
这是我目前的代码:
package com.example.flashlightapp; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class Whitelight extends Activity implements OnClickListener { Button b1 = (Button) findViewById(R.id.b3); Intent i = new Intent(this, MainActivity.class); { this.startActivity(i); } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_whitelight); } @Override public void onClick(View v) { // TODO Auto-generated method stub } }
我应该放什么
@Override public void onClick(View v) { // TODO Auto-generated method stub }
I am very new to android programming. I want to use a code that takes me to MainActivity from my current activity on a click of a Button.
Here is my current code:
package com.example.flashlightapp; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class Whitelight extends Activity implements OnClickListener { Button b1 = (Button) findViewById(R.id.b3); Intent i = new Intent(this, MainActivity.class); { this.startActivity(i); } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_whitelight); } @Override public void onClick(View v) { // TODO Auto-generated method stub } }
What should I put in
@Override public void onClick(View v) { // TODO Auto-generated method stub }
原文:https://stackoverflow.com/questions/25823083
最满意答案
Django <= 1.7
这将为您提供所有相关对象的属性名称:
links = [rel.get_accessor_name() for rel in a._meta.get_all_related_objects()]
然后,您可以使用这样的东西来获取所有相关对象:
for link in links: objects = getattr(a, link).all() for object in objects: # do something with related object instance
我花了一段时间试图弄清楚这一点,所以我可以在我的一个模型上实现一种“观察者模式”。 希望有帮助
Django 1.8+
使用
_meta.get_fields()
: https :_meta.get_fields()
参见_get_fields()
源中的_get_fields()
)Django <= 1.7
This gives you the property names for all related objects:
links = [rel.get_accessor_name() for rel in a._meta.get_all_related_objects()]
You can then use something like this to get all related objects:
for link in links: objects = getattr(a, link).all() for object in objects: # do something with related object instance
I spent a while trying to figure this out so I could implement a kind of "Observer Pattern" on one of my models. Hope it's helpful.
Django 1.8+
Use
_meta.get_fields()
: https://docs.djangoproject.com/en/1.10/ref/models/meta/#django.db.models.options.Options.get_fields (see reverse in the_get_fields()
source also)
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