android app for drawing plans

PrefaceAn excellent application is not only to have attractive features and interactions, but also to have high performance requirements. Mobile phone running Android system, although the configuration in the continuous upgrade, but still can not be compared with the PC, the PC does not have the same large memory and high-performance CPU, so in the development of Android applications can not be unlimited us

PrefaceAn excellent application is not only to have attractive features and interactions, but also to have high performance requirements. Mobile phone running Android system, although the configuration in the continuous upgrade, but still can not be compared with the PC, the PC does not have the same large memory and high-performance CPU, so in the development of Android applications can not be unlimited us

them, Nnibsize is what I call a dot pixel (100*100). An example would be clearer:* My device is 5.7inch, resolution is 1920*1080 (PX), calculate the device PPIThis is to get my device PPI. And my device was filed near the drawable? I debug my Code, I found 800*800 picture placed under-HDPI, get the size of the figure for 1467*1467, why this is the value. In the above code, I obtained a nearest pixel density, found that dm.density obtained a value of 2.75, that is, our 386 pixel density near the

Android encapsulates this approach, and we don't have permission to call it, so we can just go through the aidl and use the Java reflection mechanism to invoke the system-level approach. The following code: (note more detailed) /** * Role:-----Get the size of the package-----* @param context * @param pkgname app's package name * @param appInfo entity class for storing some information about the app/PU

View layout and Drawing Mechanism in Android To study the layout and Drawing Mechanism of the View in Android, I created a very simple App with only one Activity. The layout corresponding to the Activity is as follows: The layout file is very simple. There is

effect, of course, more than 60fps is not necessary.The performance goal of the development app is to keep 60fps (some less will not affect the user experience), which means that each frame you only have 16ms=1000/60 time to handle all the tasks (this time can be used to compare with TraceView time, not too much for example greater than 32ms, Otherwise, it should be optimized).6) Android, UI and the GPUUnd

The fluency of the Android system has been compared to iOS and is considered inferior to the latter. This aspect is related to the uneven quality of the Android device, on the other hand, and the implementation of the Android system. For example, before 3.0, the Android application UI

Two: Turn on GPU over-drawing debugging via ADB commandOf course, if you have trouble getting into the system setup every time, you can use the ADB command to turn it on and off:Turn on "Debug GPU Over-drawing":adb shell setprop debug.hwui.overdraw show 1 To turn off debug GPU over-painting:debug.hwui.overdraw false 1 You may need to restart the

Original address: http://android.xsoftlab.net/training/graphics/opengl/index.htmlIntroductionThe Android framework layer provides a number of standard tools for creating beautiful, functional UIs. However, if you want to control the drawing of the screen in more ways, or draw in a three-dimensional drawing, then you need to use other tools. The OpenGL ES API prov

by GC frequent, resulting in the card. Cause a lot of reasons for the lag, but no matter how the reason and the scene, the end is through the device screen display to reach the user, in the final analysis is a problem, so, to solve the card, we must first understand the Android system display principle.Android System Display principleThe Android display process can be summarized as follows: The

In order to use OpenGL ES drawing in an Android app, you first have to create a view container. One of the simplest methods is to implement Glsurfaceview and Glsurfaceview.renderer. Glsurfaceview A view container to display OpenGL-drawn graphics, glsurfaceview.renderer to control the drawing of graphics inside the Glsu

by GC frequent, resulting in the card. Cause a lot of reasons for the lag, but no matter how the reason and the scene, the end is through the device screen display to reach the user, in the final analysis is a problem, so, to solve the card, we must first understand the Android system display principle.Android System Display principleThe Android display process can be summarized as follows: The

class under Android. graphics is used to draw 2D vector diagrams. This package provides many classes and methods for Drawing Images on mobile phones, including canvas, while painting (Android. graphics. paint) class is like a color pencil. Different coincidences can be used to draw vector images of different colors and effects. This example uses different paint

The Double Buffer technology is mainly used for drawing and animation effects. The principle is to load resources to the buffer zone first, and then load the buffer to the View. The dual-buffer technology can effectively prevent flickering and improve the display quality. DrawView. java: Package com. example. handdraw; Import android. content. Context; Import android