Re: Question about android graphics.
On 3月31日, 下午5时27分, Dianne Hackborn hack...@android.com wrote: 2009/3/31 waterblood guoyin.c...@gmail.com if so, the Layer must have information about its position in display. But I only see it is created as the code below: Layer* layer = new Layer(this, display, client, id); status_t err = layer-setBuffers(client, w, h, format, flags); so layer only knows the windows size w,h, and format. How it knows it is relative position in display？ Well there are APIs to change the layer's values. Just look at the Surface APIs to see them at the Java level. refer to LayerBase::setPosition(x, y) --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
Re: Question about android graphics.
2009/3/31 waterblood guoyin.c...@gmail.com 1. As a multi windows systems, each window whill hold two buffers (front buffer, back buffer in surface). Is all the buffer size determined by the windows size or the display pannel size? If its size is same as the window'size, whether surface will destroyed and recreated if we resize it? It's the size of the window. The buffer is resized when the window resizes; the surface is not destroyed. 2. How to control the z-order of Layer in surface? everytime a new Layer created, it will be added to the top in surfaceflinger. So if we want jump to another exist windows, how to updat the z-order of the former window, jump-to window? Don't use surface flinger directly, use the window manager; it takes care of Z-ordering. -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
Re: Question about android graphics.
On 4月1日, 上午10时10分, Dianne Hackborn hack...@android.com wrote: 2009/3/31 waterblood guoyin.c...@gmail.com 1. As a multi windows systems, each window whill hold two buffers (front buffer, back buffer in surface). Is all the buffer size determined by the windows size or the display pannel size? If its size is same as the window'size, whether surface will destroyed and recreated if we resize it? It's the size of the window. The buffer is resized when the window resizes; the surface is not destroyed. if so, the Layer must have information about its position in display. But I only see it is created as the code below: Layer* layer = new Layer(this, display, client, id); status_t err = layer-setBuffers(client, w, h, format, flags); so layer only knows the windows size w,h, and format. How it knows it is relative position in display？ 2. How to control the z-order of Layer in surface? everytime a new Layer created, it will be added to the top in surfaceflinger. So if we want jump to another exist windows, how to updat the z-order of the former window, jump-to window? Don't use surface flinger directly, use the window manager; it takes care of Z-ordering. -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
Re: Question about android graphics.
2009/3/31 waterblood guoyin.c...@gmail.com if so, the Layer must have information about its position in display. But I only see it is created as the code below: Layer* layer = new Layer(this, display, client, id); status_t err = layer-setBuffers(client, w, h, format, flags); so layer only knows the windows size w,h, and format. How it knows it is relative position in display？ Well there are APIs to change the layer's values. Just look at the Surface APIs to see them at the Java level. -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
Question about android graphics.
Hi All, I am tring to analyse the android graphics. After reading the source in android, I still have no idea how it works. Here I list a few questions. Any reply will be welcome. 1. what is the relationship between ViewRoot and View class. As my understanding, in each window, there is only one ViewRoot, even though there are mutil View or ViewGroup shows in that window. The showing route is started by WindowManagerService as below: ViewRoot::handleAppVisibility()--ViewRoot::handleAppVisibility()-- ViewRoot::performTraversals()��--ViewRoot::draw()--view::draw() In view::draw, it will draw its data to its canvas and dispatch draw calling to its children's view. Is all view ,its children's view and their viewRoot share the same canvas for draw? 2. What is the relationship within View, canvas and Surface. To my thinking, every view will be attached a canvas and surface. And a canvas hold the bitmap for view, will the actual view drawn data will be in canvas' bitmap. After View draw its data to canvas, ViewRoot will call surface.unlockCanvasAndPost(canvas) to schedule surfaceFlinger::composeSurfaces() which do the actually display to display panel. Where is the drawn data in canvas transfer to surface front buffer or backbuffer? I cannot find the code to do that. Do different views within the same ViewRoot share the same surface? Thanks --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
Re: Question about android graphics.
1. what is the relationship between ViewRoot and View class. The ViewRoot is the root of each view hierarchy. Like you said, there is one ViewRoot per window. The ViewRoot is responsible to handling the layout and drawing of the view hierarchy. The view hierarchy is made of Views and ViewGroups. A ViewGroup is a special View that can contain other Views. Is all view ,its children's view and their viewRoot share the same canvas for draw? Yes, but that Canvas might change on every drawing operation. The ViewRoot acquires a Canvas from the underlying Surface and hands that Canvas to the top-level View. 2. What is the relationship within View, canvas and Surface. To my thinking, every view will be attached a canvas and surface. No, the Views are not attached to the Canvas nor the Surface. The window is tied to a Surface and the ViewRoot asks the Surface for a Canvas that is then used by the Views to draw onto. canvas hold the bitmap for view, will the actual view drawn data will be in canvas' bitmap. Yes. After View draw its data to canvas, ViewRoot will call surface.unlockCanvasAndPost(canvas) to schedule surfaceFlinger::composeSurfaces() which do the actually display to display panel. Yes. Where is the drawn data in canvas transfer to surface front buffer or backbuffer? I cannot find the code to do that. It's done by SurfaceFlinger. Do different views within the same ViewRoot share the same surface? Yes, except for SurfaceViews. -- Romain Guy Android framework engineer romain...@android.com Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups android-framework group. To post to this group, send email to android-framework@googlegroups.com To unsubscribe from this group, send email to android-framework+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-framework?hl=en -~--~~~~--~~--~--~---
