Develop Reference

how to Generate Dynamic Controll in android?

I want to generate Control dynamically by user specific value.
Like i have EditText for ControlId, Control Width, Control Height etc.
based on that value i want to generate control
LinearLayout L1 = new LinearLayout(this);
L1.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams L1paeam = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
L1.setLayoutParams(L1paeam);
TextView T1 = new TextView(this);
T1.setText(R.string.Dynamic_text);
L1.addView(T1);
Button B1=new Button(this);
B1.setText("Dynamic Button");
L1.addView(B1);
setContentView(L1);
In this code the control-id Layout_height and Layout_width are specified but i want them as user specified

You can add any View in view container (LinearLayout, RelativeLayout, etc) and remove those views in runtime. Create view and specify layout params for that view.

Here the solution i found.
public void generateButton(String Id,int Width,int Height,String text){
#IdRes
int id = Integer.parseInt(Id);
LinearLayout.LayoutParams L1param = new LinearLayout.LayoutParams(Width, Height);
final Button B1=new Button(this);
B1.setId(id);
B1.setText(text);
B1.setLayoutParams(L1param);
B1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Button click operation goes here
}
});
layout_main.addView(B1);
}

Android Dyanmic buttons layout

When creating dynamic buttons I would like them to stack one under the other vertically. I am not sure how to create this effect.
for(int i = 0; i <notificationArrayList.size(); i++)
{
if(i == 0)
{lp.addRule(RelativeLayout.BELOW, R.id.searchButton);}
else
{} //maybe tell the code here to stack under the lastID?
Notification oNote = notificationArrayList.get(i);
Button btn = new Button(this);
btn.setId(i);
final int id_ = btn.getId();
btn.setText(oNote.NotificationText);
btn.setBackgroundColor(Color.rgb(70, 80, 90));
rl.setLayoutParams(lp);
rl.addView(btn, lp);
}
Maybe in the else statement have it get the last id and add RelativeLayout that way?

The easiest way would be to put all the buttons in a LinearLayout and just add the LinearLayout beneath the search button. This produces easier code, but slightly worse drawing performance. Pseudocode would be like:
LinearLayout ll = new LinearLayout(context);
for(i=0; i<numButtons; i++) {
ll.addView(new Button(context));
}
RelativeLayout.LayoutParam lp = new RelativeLayout.LayoutParam();
lp.addRule(RelativeLayout.BELOW, R.id.searchButton);
relativeLayout.addView(ll,lp);

This example should give you an idea:
public class MyActivity extends Activity {
private RelativeLayout rel;
private EditText editText;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mine);
rel = (RelativeLayout) findViewById(R.id.main_rel);
editText = (EditText) findViewById(R.id.pref_edit_text);
Button button = new Button(this);
button.setText("Delete");
// create the layout params that will be used to define how your
// button will be displayed
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
// add the rule that places your button below your object (here a editText)
params.addRule(RelativeLayout.BELOW, editText.getId());
// set the layoutParams on the button
button.setLayoutParams(params);
// add button to your RelativeLayout
rel.addView(button);
}
}

managing visibility of relativelayout children

I had to implement the expand/collapse(show/hide) a particular view on click of a some other view..Finally got it working but with a small problem.
I have a relative layout with two children: first is the textview and second is a linear layout.
On the click event of the textview i set the visibility(VISIBLE or GONE) of the following linear layout.
Now the problem is that after the linear layout is visible it somehow manages to hide the textview..
I tried textview.bringToFront() but it just makes the textview overlap the first row of the linearlayout ie the textview comes on top of the linear layout content.
I tried putting the textview in a linearlayout, but it makes no difference.
I tried setting the linear layout as BELOW. All in vain..
I know the textview exists because when i click the first row(which is overlapping the textview) the click event gets fired..
All i want is that no matter what my textview should be visible and the linear layout must take its position below the textview if it is visible..
EDIT
RelativeLayout wrapperlayout = new RelativeLayout(getActivity());
//wrapperlayout.setLayoutParams(new android.widget.RelativeLayout.LayoutParams(android.widget.RelativeLayout.LayoutParams.MATCH_PARENT, android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT));
//-------------HANDLE---------------------------
TextView txtHeader = new TextView(getActivity());
txtHeader.setOnClickListener(new OnClickListener() {
#SuppressLint("NewApi")
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
TextView tv = (TextView) v;
RelativeLayout rParent = (RelativeLayout) tv.getParent();
LinearLayout lInner = (LinearLayout) rParent.getChildAt(1);
if(lInner.isShown())
{
tv.setCompoundDrawablesWithIntrinsicBounds(R.drawable.expand, 0, 0, 0);
//tv.bringToFront();
lInner.setVisibility(View.GONE);
//lInner.startAnimation(AnimationUtils.loadAnimation(getActivity(), R.anim.slide_up));
}
else{
tv.setCompoundDrawablesWithIntrinsicBounds(R.drawable.collapse, 0, 0, 0);
//tv.bringToFront();
lInner.setVisibility(View.VISIBLE);
lInner.setTop(tv.getBottom());
//lInner.startAnimation(AnimationUtils.loadAnimation(getActivity(), R.anim.slide_down));
}
}
});
txtHeader.setText("Header");
txtHeader.setCompoundDrawablesWithIntrinsicBounds(R.drawable.expand, 0, 0, 0);
txtHeader.setLayoutParams(new android.widget.LinearLayout.LayoutParams(android.widget.LinearLayout.LayoutParams.MATCH_PARENT, android.widget.LinearLayout.LayoutParams.WRAP_CONTENT));
//--------------CONTENT-------------------------
LinearLayout lContent = new LinearLayout(getActivity());
lContent.setLayoutParams(new android.widget.LinearLayout.LayoutParams(android.widget.LinearLayout.LayoutParams.MATCH_PARENT, android.widget.LinearLayout.LayoutParams.WRAP_CONTENT));
lContent.setOrientation(LinearLayout.VERTICAL);
HashMap<String, String> MySet = new HashMap<String, String>();
MySet = getData();
Iterator<String>RowItr = MySet.keySet().iterator();
int rowcnt = 0;
while (RowItr.hasNext()) {
LinearLayout lRow = new LinearLayout(getActivity());
LinearLayout.LayoutParams lparams1 = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
lRow.setLayoutParams(lparams1);
lRow.setOrientation(LinearLayout.HORIZONTAL);
TextView txtLbl = new TextView(getActivity());
txtLbl.setLayoutParams(new LinearLayout.LayoutParams(0, android.view.ViewGroup.LayoutParams.WRAP_CONTENT, 1));
TextView txtVal = new TextView(getActivity());
txtVal.setLayoutParams(new LinearLayout.LayoutParams(0, android.view.ViewGroup.LayoutParams.WRAP_CONTENT, 1));
String Lbl = RowItr.next();
txtLbl.setText(Lbl);
if(rowcnt % 2 != 0)
lRow.setBackgroundColor(Color.parseColor("#dbe4f0"));
else
lRow.setBackgroundColor(Color.parseColor("#ffffff"));
txtVal.setText(MySet.get(Lbl));
lRow.addView(txtLbl);
lRow.addView(txtVal);
lRow.setPadding(10, 10, 10, 10);
lContent.addView(lRow);
rowcnt++;
}
lContent.setVisibility(View.GONE);
wrapperlayout.addView(txtHeader);
wrapperlayout.addView(lContent);
RelativeLayout.LayoutParams rPARAMS = new RelativeLayout.LayoutParams(android.widget.RelativeLayout.LayoutParams.MATCH_PARENT, android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
//rPARAMS.addRule(RelativeLayout.ABOVE, txtHeader.getId());
//rPARAMS.addRule(RelativeLayout.BELOW, lContent.getId());
wrapperlayout.setLayoutParams(rPARAMS);

well you can store your LinearLayout as an instance variable, and simply call layout.setvisibility(View.GONE); in your onClick method. Doubt theres any other solution unless you want to save the parent(the layout that both of your views are attached to) and perform findViewById inside onClick or call getChildAt(1) orso

Got a solution.. i tried setting margins..and it all worked out well.. te handle and content both are visible without hiding any other views..

Adding dynamic views on Android

I have the following code:
scroll = (ScrollView) findViewById(R.id.scrollView1);
...
public void addItem(String str, int id) {
LinearLayout lay = new LinearLayout(this);
lay.setId(id);
TextView txt = new TextView(this);
txt.setText(str);
lay.addView(txt);
scroll.addView(lay);
}
And when i call addItem() once it's Okay, but when i call it twice or more, like this:
addItem("text1",1);
addItem("text2",2);
my app crashes :(

It's because ScrollView can only host 1 direct child.
You could create a LinearLayout as the only child of the ScrollView, and then add to the LinearLayout instead of the ScrollView in your addItem method.
scroll = (ScrollView) findViewById(R.id.scrollView1);
LinearLayout lay = new LinearLayout(this);
scroll.addView(lay);
// maybe do some more with lay here, or define it in xml instead of adding it here in the code
...
public void addItem(String str, int id) {
LinearLayout lay2 = new LinearLayout(this);
lay2.setId(id);
TextView txt = new TextView(this);
txt.setText(str);
lay2.addView(txt);
lay.addView(lay2);
}

Dynamic RelativeLayout in Android: Scroll not Working

I want to put a scroll in vertical orientation in a Relative Layout that i created programmatically. But my scroll do not work. Can anyone help me?
Here is the code that i'm using:
RelativeLayout layout = (RelativeLayout) findViewById(R.id.screen1);
for (i = 1; i < 20; i++) {
RelativeLayout.LayoutParams p = new
RelativeLayout.LayoutParams(
150,
RelativeLayout.LayoutParams.WRAP_CONTENT
);
layout.setScrollContainer(true);
ScrollView vscroll = new ScrollView(this);
vscroll.setFillViewport(true);
layout.setVerticalScrollBarEnabled(true);
layout.addView(vscroll);
p.addRule(RelativeLayout.BELOW, i-1);
p.addRule(RelativeLayout.CENTER_HORIZONTAL);
Button buttonView = new Button(this);
buttonView.setId(i);
buttonView.setText(i);
buttonView.setLayoutParams(p);
buttonView.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
Dialog(((Button)arg0).getId());
} });
layout.addView(buttonView, p);
}

I think you need to be adding your buttonViews to the ScrollView instead of the layout. ScrollView is a container View (like RelativeLayout). I think what your code is doing is adding a 0 height ScrollView to the top of your RelativeLayout, then a button after that. Since the button is not in the ScrollView, your 20 buttons won't scroll.

Try as below it may help
vscroll.addView(button);