I'm trying to change my checkbox dynamically.
for some reason the app throw my an exception.
what am I doing wrong?
this is my java code:
package com.school.commtest;
import android.app.Activity;
import android.os.Bundle;
import android.widget.CheckBox;
import android.widget.TableLayout;
import android.widget.TableRow;
public class OtherPlacesMenu extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
CheckBox c1 = (CheckBox)this.findViewById(R.id.schools);
c1.setChecked(true);
setContentView(R.layout.otherplacesmenu);
}
}
and this is the xml:
<?xml version="1.0" encoding="utf-8"?>
<TableLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/table">
<TableRow android:layout_height="fill_parent" android:layout_width="wrap_content" android:id="#+id/tableRow1">
<CheckBox android:text="School" android:id="#+id/schools" android:layout_width="wrap_content" android:layout_height="wrap_content"></CheckBox>
</TableRow>
<TableRow android:layout_height="fill_parent" android:layout_width="wrap_content" android:id="#+id/tableRow2">
<CheckBox android:text="Supermaker" android:layout_height="wrap_content" android:id="#+id/supermarkets" android:layout_width="wrap_content"></CheckBox>
</TableRow>
<TableRow android:layout_height="fill_parent" android:layout_width="wrap_content" android:id="#+id/tableRow3">
<CheckBox android:text="Gardens" android:layout_height="wrap_content" android:id="#+id/gardens" android:layout_width="wrap_content"></CheckBox>
</TableRow>
</TableLayout>
I'm sure its a simple question, but I cannot find the answer anywhere.
p.s.
I can't set the value of the checkbox to be true at the xml because I would later want to change the checkbox from the user setting.
10x!
Usually you should post the exception message when asking a question like this, but it looks like your problem is that you're trying to findViewById before you setContentView. Your view doesn't exist to be found when you look for it.
Related
I am trying to show a simple listView with an image, a large text and a small text in each list item. I have coded the following but when I run the app, it gives a NullPointerException. For the method i have used, I do not need to findviewbyid so I'm not sure what I am doing to give this error. Anyone know?
This is my MenuPage.java file
import android.app.Activity;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
public class MenuPage extends ListActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String[]values=new String[]{"Coffee","Steak","Ice Cream"};
String[]prices=new String[]{"$4.99","$21.99","$12.99"};
setListAdapter(new ArrayAdapter<String>(this,R.layout.activity_main,R.id.values, values));
setListAdapter(new ArrayAdapter<String>(this,R.layout.activity_main,R.id.prices, prices));
}
}
this is my menu.xml for the java file above:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<ImageView
android:id="#+id/ic_launcher_movies"
android:layout_width="50px"
android:layout_height="50px"
android:layout_marginLeft="4dp"
android:layout_marginRight="10px"
android:layout_marginTop="2dp"
android:src="#drawable/items"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true">
</ImageView>
<TextView
android:id="#+id/values"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#+id/values"
android:textSize="25sp"
android:layout_alignParentLeft="true"
android:layout_marginLeft="64dp"
android:layout_alignParentTop="true"
android:layout_marginTop="0dp"
android:minHeight="120dp">
</TextView>
<TextView
android:id="#+id/prices"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#+id/prices"
android:textSize="10sp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginTop="120dp"
android:layout_marginLeft="65dp">
</TextView>
also, I created an xml with the drawables for the images i want to use;
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:duration="30"
android:drawable="#drawable/coffee"/>
<item
android:duration="30"
android:drawable="#drawable/steak"/>
<item
android:duration="30"
android:drawable="#drawable/icecream"/>
and my logcat gives this error
any help would be appreciated! thank you
I think the problem in the menu layout file
android:text="#+id/values"
try to write some text or specify link to string resource like
android:text="#string/my_button_text"
And when you call setListAdpate two times you ovirwrite first adapter with new. Have a look to example here
ListActivity
I have successfully created a sample card on android wear by referring following tutorial https://developer.android.com/training/wearables/ui/cards.html
But my sample card doesn't minimize on down swipe.
This is the output I'm getting
I want some thing like this
and when I swipe down card will minimize like this
Just like media player app working on wearable!
Can anyone help me with this? I have just started learning development for wearable.
Here is my code
package com.example.cardsample;
import android.app.Activity;
import android.os.Bundle;
import android.support.wearable.view.CardScrollView;
import android.view.Gravity;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.rect);
CardScrollView cardScrollView = (CardScrollView)
findViewById(R.id.card_scroll_view);
cardScrollView.setCardGravity(Gravity.BOTTOM);
}
}
rect.xml
<android.support.wearable.view.BoxInsetLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#drawable/ic_full_sad"
android:layout_height="match_parent"
android:layout_width="match_parent">
<android.support.wearable.view.CardScrollView
android:id="#+id/card_scroll_view"
android:layout_height="match_parent"
android:layout_width="match_parent"
app:layout_box="bottom">
<android.support.wearable.view.CardFrame
android:layout_height="wrap_content"
android:layout_width="fill_parent">
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:orientation="vertical"
android:paddingLeft="5dp">
<TextView
android:fontFamily="sans-serif-light"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:text="Heading"
android:textColor="#color/black"
android:textSize="20sp"/>
<TextView
android:fontFamily="sans-serif-light"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:text="description"
android:textColor="#color/black"
android:textSize="14sp"/>
</LinearLayout>
</android.support.wearable.view.CardFrame>
</android.support.wearable.view.CardScrollView>
</android.support.wearable.view.BoxInsetLayout>
I think what you are looking for is a notification: https://developer.android.com/training/wearables/notifications/creating.html
A notification shows the title when its minimized and when you swipe up it shows the full text or your custom layout (https://developer.android.com/training/wearables/apps/layouts.html).
I'm very new to Android developing.
When I create a new project and try to simply add a button using the graphical layout and try refering to it it won't find it.
Sometimes doing a "Clean..." works sometimes it doesn't. Also sometimes restarting eclipse works and sometimes it doesn't.
Is eclipse really that unstable or am I doing something wrong?
Also I should mention that I did go over all the posts of other people (I know this question is being asked alot) but I still haven't found an asnwer
Here is the .java file:
package com.example.testapp;
import com.example.testapp.R;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.Button;
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b = (Button) findViewById(R.id.button1);
}
}
and here is the xml file:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="#string/hello_world"
tools:context=".MainActivity" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginTop="14dp"
android:text="Button" />
</RelativeLayout>
I am new to Android/java programming. I really have no clue what I am doing, and would like a little help. What I am trying to do is build a form very similar to the one below. I have already put in all of the layout, and strings information, but I am having trouble with the functions. The error that I am getting is View cannot be resolved to a type line 14. I am using eclipse to help me program this app. Here is my main.xml, and MadisonStudios.java file's contents as well.
http://mobile.tutsplus.com/tutorials/android/android-sdk-creating-forms/
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/welcome" />
<EditText
android:id="#+id/EditTextName"
android:layout_height="wrap_content"
android:hint="#string/name"
android:inputType="textPersonName"
android:layout_width="fill_parent">
</EditText>
<EditText
android:id="#+id/EditTextEmail"
android:layout_height="wrap_content"
android:hint="#string/email"
android:inputType="textEmailAddress"
android:layout_width="fill_parent">
</EditText>
<Spinner
android:id="#+id/SpinnerStatus"
android:layout_height="wrap_content"
android:prompt="#string/status"
android:layout_width="fill_parent"
android:entries="#array/statuslist">
</Spinner>
<EditText
android:id="#+id/EditTextFeedbackBody"
android:layout_height="wrap_content"
android:hint="#string/changebody"
android:inputType="textMultiLine"
android:lines="5"
android:layout_width="fill_parent">
</EditText>
<Button
android:id="#+id/ButtonSendChange"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:onClick="sendChange"
android:text="#string/changebutton">
</Button>
</LinearLayout>
MadisonStudios.java
package com.madisonstudios.supportapp;
import android.app.Activity;
import android.os.Bundle;
public class MadisonStudios extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
public void sendChange(View button) {
// Do click handling here
}
}
import android.view.View;
Add this line in import statements..
You should import it. If you are using Eclipse, press Ctrl+Shift+o.
I load url, for example mail.google.com, into webview in my app, and scrolling on web-page so slow! Tested on Samsung GalaxyTab 10.1, Motorola Droid X, Acer Liquid, etc.
Why?
Parameters that I try use:
webView.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);
webView.setRenderPriority(RenderPriority.HIGH);
add android:hardwareAccelerated="true" to the tag in your manifest.
Remove background image of the webview if you put it and also see if you used heavy size images in progress or loading or other images of heavy size reduce their sizes or remove it
This is a main.xml file
This code is a scrolling only, any where u can use
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:fillViewport="true">
<LinearLayout android:id="#+id/LinearLayout01"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TextView android:id="#+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a header"
android:textAppearance="?android:attr/textAppearanceLarge"
android:paddingLeft="8dip"
android:paddingRight="8dip"
android:paddingTop="8dip"></TextView>
<TextView android:text="#+id/TextView02"
android:id="#+id/TextView02"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_weight="1.0"></TextView>
<LinearLayout android:id="#+id/LinearLayout02"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<Button android:id="#+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Submit"
android:layout_weight="1.0"></Button>
<Button android:id="#+id/Button02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Cancel"
android:layout_weight="1.0"></Button>
</LinearLayout>
</LinearLayout>
</ScrollView>
This is .java file
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
public class ScrollViewActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView view = (TextView) findViewById(R.id.TextView02);
String s="";
for (int i=0; i < 200; i++) {
s += "Android Market ";
}
view.setText(s);
}
}