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Created June 15, 2015 18:24
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Android for Beginners : Simplified ImageView class
/**
* Displays an image, such as an icon.
*/
public class ImageView extends View {
// Resource ID for the source image that should be displayed in the ImageView.
private int mImageId;
// Context of the app
private Context mContext;
/**
* Constructs a new ImageView.
*/
public ImageView(Context context) {
mImageId = 0;
mContext = context;
}
/**
* Sets the source image in the ImageView.
*
* @param imageId is the resource ID of the image to be displayed.
*/
public void setImage(int imageId) {
mImageId = imageId;
}
}
@rejero
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rejero commented Dec 31, 2016

@Stannisseaworth I know how it feels, had the same issue when I first started learning programming. Will try to explain it non-programming way. A constructor is like the laws of a society. Before you create the society (objects), you have to define the laws what you can eat, do, etc etc (parameters and arguments) and write them down on an official piece of paper (magic methods). The society would then run and revolved based on those pieces of paper and laws. This is why they are called constructors. Hope I got this right.

@ardakazanci
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ardakazanci commented Feb 3, 2017

Correction ;
public ImageView(Context context) { super(context); mImageId = 0; mContext = context; }

@krishsam02
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in place of setImage method there is src to set image.

@TrentonMGT
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TrentonMGT commented Jul 23, 2017

A constructor is a method that is called or invoked when the object is created. A class is just the blueprint of an object.

@Maxwe1
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Maxwe1 commented Feb 5, 2018

helpful ..thanks

@badrddinb
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Simple example helpful!

@alsafi988
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nice

@Maensh
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Maensh commented Mar 8, 2018

nice

@sal77ama
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nice

@chayanbobra13
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helpful

@Eduese
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Eduese commented May 21, 2018

Seems errors noticed by our predecessors have been corrected. Nice work

@tooptooptoop
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Thanks.

@moiyd
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moiyd commented Sep 29, 2018

thanks

@nurbijoy
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Thanks

@djalilo24
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TNX

@YassineOuardini
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thanks ♥

@avinabX
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avinabX commented Aug 11, 2019

please can anyone explain why the member variables they used were declared private access modifier
private int mImageId;

**private** Context mContext;

@LaszloLajosT
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please can anyone explain why the member variables they used were declared private access modifier
private int mImageId;

**private** Context mContext;

I copied the answer from the other site:

What is difference between Private and Protected?

Private get only used in his class , but protected can used in his class and in the same package and derived class

@faroukelhamdi
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Was here!

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