This means that when Value changes, Text will also change accordingly. A bi-directional binding looks a bit different.

这意味着当Value改变的时候，Text也会相应改变。

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With targeted bit speed and specialized MWD components, the SRT provides efficient directional drilling at a lower cost than rotary-steerable systems.

高效钻速与专业化的MWD组件，使得SRT较于常规型旋转导向系统能够以更低成本完成更加高效的定向钻进。

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Also, the center Select button, in the middle of the directional arrows, is a bit hard to use, as the circle button is quite small.

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Scaling the Apple Maps app to this screen size would be a bit more challenging, as you can see here from the size of the directional text.

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